Another HUGE thanks to you Both Pierre and Thomas. You two work to provide so much valuable information that just is not available anywhere else. And as always Pierre, your absolute no BS delivery of the facts is appreciated more than I can express. Thank you!
Dear Pierre, i have this problem with my 1984 euro 380sl. The idle contol valve gets 12 volts instead of 4,5 volts. So my engine stalls when hot! Could this be the idle control unit? Many thank! Greetings fom Belgium
There are actually SIX electrolytic capacitors. 4 Radial (standing up) and 2 Axial (laying flat). The axial ones are close to each other and are blue striped, with one wire coming out of each end. These fail at the same rate. The transistors too can fail, there are about 4 or 5 of them depending on model, etc. These are the small, "D" shaped three-leg devices standing upright on the board, usually with a blue spacer underneath. These control the different "stages" of idle speed, or the drop in idle speed from a cold start I have found. These should also be replaced in my experience. (however one of the transistors is obsolete and no longer made). Other than that, ANY of the resistors (flat-laying, small, cylinders with colorful stripes on them) themselves can also fail, but usually don't and are easy to check if you see one looks burned/cracked. UPDATE: After doing some searching I found a suitable alternative to the one obsolete transistor. I believe the "BC139" Bipolar Transistor (PNP) by STMicroelectonics to be a suitable replacement. SO, If your unit has a failure of the obsolete transistor, or one of the IC's (chips) are bad, then you would be best served getting a new/rebuilt unit. Otherwise they are indeed very rebuildable. Of course also check for cracked solder joints and cracked/fried traces on the board. Any exposed traces (copper looking) that are missing their green coating on the board should be considered VERY suspect (as this normally means that area got very hot, most likely because of a "short" somewhere) and inspected carefully for breaks. These breaks are very hard to spot sometimes, especially so since the background is similarly colored. Just adding my $0.02 to try and help out someone who was as frustrated as I was the first time I attempted this repair. Thanks Pierre for this great video!!
Hi Jonathan, I just came across your post here. I’ve been chasing an erratic idle on my 1983 380sl. Car starts fine, just when it reaches operating temperature it starts with inconsistent erratic idle. Surging from 800-1200rpm. I’ve checked temperature sensors and they’re not the cause I’m sure. In your experience can an idle control module partially fail so as to cause erratic idling. If so, how would you check?
@@petercastro2413 Yea it can... but i would start with replacing the o2 sensor and setting the mixture correctly before really focusing on the idle control module. Though, if that has never been looked at, then it must also be done. Even just the mixture being slightly off can cause the surging you are talking about. Usually only happens during the warming-up phase though.
Jonathan, thanks for your reply! I do have a slight rich mixture. When I pulled my spark plugs they were black, not horrible but enough. I have an ocillascope and the signal shows the frequency valve trying to lean things out. I plugged it in to port 3 and 2 (ground) of the x11. I’ve also tapped into the ECU where I can get a nice square wave so I can do fine adjustment. The icm and iscv are new. I’ll do the adjustments see if that fixes my issue. I need to pass smog! @@Johnathan_Waters
I've literally never had luck getting questions answered here but I think usually it's cuzza I'm not e'splaining things correctly. So. This may be TMI but better than TLI. 1983 380sl, sat in a garage 4 years b4 I bought, 2 owners, well maintained. 1st emptied tank best I could, stableized, filled with fresh gas. Ran great for a week then crappy. I had to feather throttle ¼ mile to get any speed. Replaced fuel tank, fuel lines, liqui Moli, new (reman) fuel distributor, fuel filter, fuel pump, kickdown switch, entire AC system (literally all of it), all fuses, plugs, wires, distrib/cap/coil, and more. Relays seemed fine. Finally, it ran great. Periodically though, it idles so low in drive that at a light I worry about a stall, esp w/ AC on. Then, green light, I "sometimes" have to feather gas. Some cat said "maybe idles too low cuz new refrigerant is thicker," decent point so we bled some, added some - no huge change. After a drive, I pull in garage, put in park and before I shut it off it'll idle @ 1700+. So now I start looking next at the Idle Control Unit and/or the idle Control Valve. One is $230 almost universally, the other runs between $25 to one no higher rated for like $500. BTW, the OVP relay seems to be fine - had an extra. All good. Should I replace the ICV for under $100 or icu for $230? Also, I know how to solder, and have the stuff - more detailed guidance (magnified, explained) would earn you a bag of Charms Blow Pops - THEE best sucker. Idears??
I love this video, even though my cars are ‘75 and ‘80, as you know Pierre. The comments here are gold! So much interesting information. My father in law was an audio visual tech when he was alive, and a darn good one. My husband learned a little from him. It’s definitely worth a try to resolder and rebuild some of these control units. My ‘75 450SEL cold engine idle is very high, almost 1,000! I just recently changed all the little rubber vacuum lines (the black connectors) in the engine compartment- the heating system ones, under the air cleaner vacuum ports off of intake throttle area, and the three vacuum solenoids lines on the firewall. I didn’t get the main one at the back of the motor, yet. I haven’t had a chance to test drive to see if the high idle went away, we got dumped on with snow. I don’t think the idle will change much from the vacuum line r&r but it’s a step in the right direction.
I've repaired the soldering spots on my W124's Fuel Pump and OVP relays and on the internal terminals of the KE computer, changing two capacitors too; no engine fails since then.
@@mercedesclassicswithpierre1753 inernally where the pins match to the blades that are in fact soldered to the little board; an almost imperceptible oxidation at the contact point; I've cleaned the metal and soldered all of them. Specifically at the fuel pump relay, it seemed to not be receiving the RPM signal at pin "TD", from the AC compressor unit, pin 2. I'll add photos to this reply, just a moment please.
Great video! I have an 1984 SEL that will not stay running without bypassing the fuel pump relay because the relay is not receiving a tach signal. The instrument panel tachometer is inoperative also. Tach signal is from the distributor to the ignition control module and to a terminal block that connects to the test connector, fuel pump relay, idle control module, and tachometer. Ignition control module was replaced but problem persist. Tachometer still does not work with the fuel pump relay removed and bypassed. Some state that the tach signal can be checked with a multimeter or dwell meter. ProgRama tells me that is not true and it requires a scope. Could the idle control module be shorting out the tach signal causing the problem?
I have a question. I replaced the icv and the rpms started jumping 1000 1200. I then replace the 3 transistors on the idle control unit and the rpms came back to normal. On a warm engine the idle is fine but on cold start the rpms stay under 500 around 400. On cold start the rpms should rise untill engine warms up and settles the rpms at 550, now is the idle control unit also responsible for cold start rpms? Should I just get a rebuilt one?
Hi your videos are really good. i have a 1991 300esl car turn off wen i driving locks like idler control problems how can i see if the part is not working. please
Our problem 1991 500 sl European model. Start car it idles fine, go for a ride idle goes to 2000 ,fuel consumption gauge stops. Car in garage starts idles fine I unplug the ICV that I have cleaned 2 times idle goes to 2000. I plug ICV back in it idles back to normal. Is the ICV not working properly or whatever controls the ICV not working. Appreciate any input. Thank You
I imported in Europe a 1989 560 SL. When it is cold the injectors work fine. As the car warms up the right side injectors start to give less and less fuel and in the end the car dies. Also the manifold gets extremely hot. Any ideas?
hello pierre, i've had you answer several questions on my 1984 500sel. i changed the iac valve and cleaned both with carb cleaner and both work freely now i have a spare. to refresh your memory the problem was low idle cold and high idle warm and once in awhile it behaves. i replaced the coolant temp sensor (on the back pass.side of engine) now i just replaced the idle control module with a used programa module from a wrecked car with the same service numbers. now it has a surging idle and no cold start high idle and seems to be rich. what now??
Hi Pierre - Great channel thanks! - just bought a 85 380sl and it is idling high around 15 to 20 I took out idle air control valve and cleaned it out with carb cleaner but no help I pulled out the OVP from above the fuse box and checked the fuse in it and that was good - how can I check to know if OVP is good? Also I thought I pulled out the Idle control unit (behind glove box) but found out it was the blower motor speed control unit LOL ( they look similar) I will go out now and look for that idle control unit and inspect it as you showed in this video. Having fun learning and puttin around on my new toy - any input here on my issue would be great - Thank You
Hello, Ernie D and thank YOU so much for your question(s), we want to answer you as quickly as possible. By signing in our Patreon www.patreon.com/thomaspolk page and making a donation of $10 your are assured of a 24 hour email response from Pierre. If you are already a $10 member please mention along with your question.
I have later model of 126. 1990 having problem with idle staying between 700 to just below 1000 rpm. I changed everything I can think of in terms with vacuum leak. All the way to intake manifold gaskets upper and connection between upper and lower. How do I check to see if idle speed control unit is bad or idle control valve is bad?
Hi, I had a issue once, it was the terminals in the fuel pump actuator, I had to solder 3 cm on new wire and cover with thermal shrink tube, just pay attention to the position of the color wires when you open the plug. No problem since then, but maybe the actuator can fail also, I never checked the Idle Control Unit on my W124 so until it fails I keep calm. Thanks. AC
Hi there, i got a 300 se 89', first changed my ecu because rain water goes in side of it and it s been broken, now i got another used ecu to my car, it has a one problem, when the car gets warm idle becomes rough it goes between 5 and 10 on tacho, now i turned off idle control valve, but this problem couses from idle control valve or used new ecu?
My 1990 560SEL 126 has a constant surging idle that no mechanic in my area has been able to fix its very sad it use to surge for 5-10 min. On startup then I could drive it but the last mechanic reset something and now surge doesn't go away could it be the module or the valve or a vacuum leak? I've given up on it
Tony Light 🤦♂️...so many guesswork mechanics out there trying to fidget with these cars when it’s just aging electronics that can be rebuilt with a soldering iron and Mouser catalog. I hope they didn’t take you to the cleaners while learning on your car...
Hello, +Tony Light and thank YOU so much for your question(s), we want to answer you as quickly as possible. By signing in our Patreon www.patreon.com/thomaspolk page and making a donation of $10 your are assured of a 24 hour email response from Pierre. If you are already a $10 member please mention along with your question.
I have a european w126 380sel and im experiencing high idle plus the abs light. What are my chances finding a replacement or should i try and repair it? Sometimes i get idle as high as 1.7k rpm and its really annoying especially when coming to a stop. Thank you
Mercedes Classics with Pierre Hedary i did replace the overvoltage relay plus the idle control module and it didnt change amything, the abs light is still on. Also the idle control valve has 2 wires one of them connected to the body and the other one goes to the bottom left corner fuse. What am i missing here ?Im really bummed what else can i try?
Hi Pierre, I own a '89 560 SEL and I had this problem for years now and no local mechanic have being able to help me and the local Mercedes dealer's suggestion is for me to buy a new car, me my car idle rough ever since I change the fuel pumps because one of them was leaking, I tried everything, change spark plugs and wires, change the fuel filter, fuel distributor, change the idle control, and I just ran out of ideas because the repairs manuals that I have are just not helping.
Pierre I am considering buying a 1984 1 owner from the owner a 1984 300sd turbo would this car have this idle control issue . It only has 30995 miles. And what would be a fair price to offer her always stored inside but not driven in several years. I enjoy your channel very much. Robert here from op ks
no, they almost always cause outright failure of the unit with high idle speed. Low idle is usually related to the fuel system being over pressurized. Extremely high control pressures choke the air flap.
I have an issue with my 1984 500 SEC Euro market car that misfires upon startup, then after about 5 seconds of running it smooths out and isles at 550 RPM when cold. Then, as the engine warms up, the idle rises and usually stops rising at around 1500 RPM but occasionally can be as high as 2000 RPM. I suspect that the high idle is idle control related. I assume that the misfire upon startup is related to a different issue. I’m hoping that the misfire issue will be solved by replacing parts that I was intending to replace anyway due to the car’s age and it’s higher mileage. What are your thoughts?
Hello, +Spencer Tarter and thank YOU so much for your question(s), we want to answer you as quickly as possible. By signing in our Patreon www.patreon.com/thomaspolk page and making a donation of $10 your are assured of a 24 hour email response from Pierre. If you are already a $10 member please mention along with your question.
Spencer, 2 things. the high idle is likely the idle control unit. the difficult start/miss might be a bad fuel pressure accumulator, or , possibly several injectors that are bleeding off.
Hello, hamshank29 and thank YOU so much for your question(s), we want to answer you as quickly as possible. By signing in our Patreon www.patreon.com/thomaspolk page and making a donation of $10 your are assured of a 24 hour email response from Pierre. If you are already a $10 member please mention along with your question.
How many folks have had their cars made worse by mechanics trying to fix an electrical problem with a mechanical solution? Thankfully, my dealership has a 35 year veteran Benz tech. who lights up when he sees my A124 pull in the garage. These cars are different than the new ones and the number of people qualified to touch them without “making the patient worse” is dwindling 😢
I do enjoy your videos! However I wish you would show more hands on repair. I also like how your hands are never clean like mine! How bout that Kent with his french manicured nails though? Or are they lee press-on
kent has his green gloves i dont have issue with a mechanic wearing gloves..u need to protect your money maker. Plus no one wants dirty hands in a car...great video tho
Another HUGE thanks to you Both Pierre and Thomas. You two work to provide so much valuable information that just is not available anywhere else. And as always Pierre, your absolute no BS delivery of the facts is appreciated more than I can express. Thank you!
I'm glad someone can use this information! (:(:
Brilliant again, very complex content explained so well.
Thank you Pierre. This is very helpful.
you're welcome!
Hello, how is the way to change the Mercedes 560 engine seats? We want an explanation or a practical video
Dear Pierre, i have this problem with my 1984 euro 380sl. The idle contol valve gets 12 volts instead of 4,5 volts. So my engine stalls when hot! Could this be the idle control unit?
Many thank! Greetings fom Belgium
There are actually SIX electrolytic capacitors. 4 Radial (standing up) and 2 Axial (laying flat). The axial ones are close to each other and are blue striped, with one wire coming out of each end. These fail at the same rate. The transistors too can fail, there are about 4 or 5 of them depending on model, etc. These are the small, "D" shaped three-leg devices standing upright on the board, usually with a blue spacer underneath. These control the different "stages" of idle speed, or the drop in idle speed from a cold start I have found. These should also be replaced in my experience. (however one of the transistors is obsolete and no longer made). Other than that, ANY of the resistors (flat-laying, small, cylinders with colorful stripes on them) themselves can also fail, but usually don't and are easy to check if you see one looks burned/cracked.
UPDATE: After doing some searching I found a suitable alternative to the one obsolete transistor. I believe the "BC139" Bipolar Transistor (PNP) by STMicroelectonics to be a suitable replacement.
SO, If your unit has a failure of the obsolete transistor, or one of the IC's (chips) are bad, then you would be best served getting a new/rebuilt unit. Otherwise they are indeed very rebuildable. Of course also check for cracked solder joints and cracked/fried traces on the board. Any exposed traces (copper looking) that are missing their green coating on the board should be considered VERY suspect (as this normally means that area got very hot, most likely because of a "short" somewhere) and inspected carefully for breaks. These breaks are very hard to spot sometimes, especially so since the background is similarly colored. Just adding my $0.02 to try and help out someone who was as frustrated as I was the first time I attempted this repair. Thanks Pierre for this great video!!
Thank you for your addition, excellent information. Actually, I think YOU should have been the one doing this video!
@@560sec7 I keep hearing the same thing! I just have a weak stomach when it comes to the internet!
Hi Jonathan, I just came across your post here. I’ve been chasing an erratic idle on my 1983 380sl. Car starts fine, just when it reaches operating temperature it starts with inconsistent erratic idle. Surging from 800-1200rpm. I’ve checked temperature sensors and they’re not the cause I’m sure. In your experience can an idle control module partially fail so as to cause erratic idling. If so, how would you check?
@@petercastro2413 Yea it can... but i would start with replacing the o2 sensor and setting the mixture correctly before really focusing on the idle control module. Though, if that has never been looked at, then it must also be done.
Even just the mixture being slightly off can cause the surging you are talking about. Usually only happens during the warming-up phase though.
Jonathan, thanks for your reply! I do have a slight rich mixture. When I pulled my spark plugs they were black, not horrible but enough. I have an ocillascope and the signal shows the frequency valve trying to lean things out. I plugged it in to port 3 and 2 (ground) of the x11. I’ve also tapped into the ECU where I can get a nice square wave so I can do fine adjustment. The icm and iscv are new. I’ll do the adjustments see if that fixes my issue. I need to pass smog! @@Johnathan_Waters
Thank you matey,very much appreciated
I've literally never had luck getting questions answered here but I think usually it's cuzza I'm not e'splaining things correctly. So. This may be TMI but better than TLI.
1983 380sl, sat in a garage 4 years b4 I bought, 2 owners, well maintained. 1st emptied tank best I could, stableized, filled with fresh gas. Ran great for a week then crappy. I had to feather throttle ¼ mile to get any speed. Replaced fuel tank, fuel lines, liqui Moli, new (reman) fuel distributor, fuel filter, fuel pump, kickdown switch, entire AC system (literally all of it), all fuses, plugs, wires, distrib/cap/coil, and more. Relays seemed fine. Finally, it ran great. Periodically though, it idles so low in drive that at a light I worry about a stall, esp w/ AC on. Then, green light, I "sometimes" have to feather gas. Some cat said "maybe idles too low cuz new refrigerant is thicker," decent point so we bled some, added some - no huge change.
After a drive, I pull in garage, put in park and before I shut it off it'll idle @ 1700+.
So now I start looking next at the Idle Control Unit and/or the idle Control Valve. One is $230 almost universally, the other runs between $25 to one no higher rated for like $500. BTW, the OVP relay seems to be fine - had an extra. All good.
Should I replace the ICV for under $100 or icu for $230? Also, I know how to solder, and have the stuff - more detailed guidance (magnified, explained) would earn you a bag of Charms Blow Pops - THEE best sucker. Idears??
I love this video, even though my cars are ‘75 and ‘80, as you know Pierre. The comments here are gold! So much interesting information. My father in law was an audio visual tech when he was alive, and a darn good one. My husband learned a little from him. It’s definitely worth a try to resolder and rebuild some of these control units.
My ‘75 450SEL cold engine idle is very high, almost 1,000! I just recently changed all the little rubber vacuum lines (the black connectors) in the engine compartment- the heating system ones, under the air cleaner vacuum ports off of intake throttle area, and the three vacuum solenoids lines on the firewall. I didn’t get the main one at the back of the motor, yet.
I haven’t had a chance to test drive to see if the high idle went away, we got dumped on with snow. I don’t think the idle will change much from the vacuum line r&r but it’s a step in the right direction.
the cold idle is fine at 1000. they are supposed to be like that.
Mercedes Classic with Pierre Hedary thanks!
I forgot to mention. I made a cold start up video on my channel of the SEL if you have time to watch. Thanks
I've repaired the soldering spots on my W124's Fuel Pump and OVP relays and on the internal terminals of the KE computer, changing two capacitors too; no engine fails since then.
So you were able to repair both of them? on what terminal did they fail. i would like to know so I can repair them.
@@mercedesclassicswithpierre1753 inernally where the pins match to the blades that are in fact soldered to the little board; an almost imperceptible oxidation at the contact point; I've cleaned the metal and soldered all of them. Specifically at the fuel pump relay, it seemed to not be receiving the RPM signal at pin "TD", from the AC compressor unit, pin 2.
I'll add photos to this reply, just a moment please.
www.kizoa.com/Montagem-Vídeo/d244028763k1629329o1l1/ovp--ke-board
unfortunately I forgot to take pictures of the fuel pump relay...
Thanks
Great video! I have an 1984 SEL that will not stay running without bypassing the fuel pump relay because the relay is not receiving a tach signal. The instrument panel tachometer is inoperative also. Tach signal is from the distributor to the ignition control module and to a terminal block that connects to the test connector, fuel pump relay, idle control module, and tachometer. Ignition control module was replaced but problem persist. Tachometer still does not work with the fuel pump relay removed and bypassed. Some state that the tach signal can be checked with a multimeter or dwell meter. ProgRama tells me that is not true and it requires a scope. Could the idle control module be shorting out the tach signal causing the problem?
I have a R107 500sl 1983 model I couldn’t locate the OVP relay, it is not inbthe fuse box area. Can you help please
I have a question. I replaced the icv and the rpms started jumping 1000 1200. I then replace the 3 transistors on the idle control unit and the rpms came back to normal. On a warm engine the idle is fine but on cold start the rpms stay under 500 around 400.
On cold start the rpms should rise untill engine warms up and settles the rpms at 550, now is the idle control unit also responsible for cold start rpms?
Should I just get a rebuilt one?
Hi your videos are really good. i have a 1991 300esl car turn off wen i driving locks like idler control problems how can i see if the part is not working. please
Our problem 1991 500 sl European model. Start car it idles fine, go for a ride idle goes to 2000 ,fuel consumption gauge stops. Car in garage starts idles fine I unplug the ICV that I have cleaned 2 times idle goes to 2000. I plug ICV back in it idles back to normal. Is the ICV not working properly or whatever controls the ICV not working. Appreciate any input. Thank You
Hi. I have a w126 280se. Issue with idle surge and power loss. Could you please help me with this issue. Thanks
Than you. Still cant decide between a w116 w126
I imported in Europe a 1989 560 SL. When it is cold the injectors work fine. As the car warms up the right side injectors start to give less and less fuel and in the end the car dies. Also the manifold gets extremely hot. Any ideas?
We have a 85 380 SE. I’m in idle hell!!!
hello pierre, i've had you answer several questions on my 1984 500sel. i changed the iac valve and cleaned both with carb cleaner and both work freely now i have a spare. to refresh your memory the problem was low idle cold and high idle warm and once in awhile it behaves. i replaced the coolant temp sensor (on the back pass.side of engine) now i just replaced the idle control module with a used programa module from a wrecked car with the same service numbers. now it has a surging idle and no cold start high idle and seems to be rich. what now??
Hello I have a 560 sl mercedes benz whit Hi rpm in ralenti about 1100 to 1300 how can I correct the problem?
Hi Pierre - Great channel thanks! - just bought a 85 380sl and it is idling high around 15 to 20 I took out idle air control valve and cleaned it out with carb cleaner but no help I pulled out the OVP from above the fuse box and checked the fuse in it and that was good - how can I check to know if OVP is good? Also I thought I pulled out the Idle control unit (behind glove box) but found out it was the blower motor speed control unit LOL ( they look similar) I will go out now and look for that idle control unit and inspect it as you showed in this video. Having fun learning and puttin around on my new toy - any input here on my issue would be great - Thank You
Hello, Ernie D and thank YOU so much for your question(s), we want to answer you as quickly as possible.
By signing in our Patreon www.patreon.com/thomaspolk page and making a donation of $10 your are assured of a 24 hour email response from Pierre.
If you are already a $10 member please mention along with your question.
I have later model of 126. 1990 having problem with idle staying between 700 to just below 1000 rpm. I changed everything I can think of in terms with vacuum leak. All the way to intake manifold gaskets upper and connection between upper and lower. How do I check to see if idle speed control unit is bad or idle control valve is bad?
do you have the part# for the 3 small transistors on a 1983 380 sl idle control module
Hi, I had a issue once, it was the terminals in the fuel pump actuator, I had to solder 3 cm on new wire and cover with thermal shrink tube, just pay attention to the position of the color wires when you open the plug. No problem since then, but maybe the actuator can fail also, I never checked the Idle Control Unit on my W124 so until it fails I keep calm. Thanks. AC
that's very cool that you were able to diagnose and repair it....it was also good yopu were able to fin the issue.
Hi, my car is idling low, when I shake my ovp relay it sounds like it's dead. And I have a euro 500sec. Where can I find these relays?
Hi there, i got a 300 se 89', first changed my ecu because rain water goes in side of it and it s been broken, now i got another used ecu to my car, it has a one problem, when the car gets warm idle becomes rough it goes between 5 and 10 on tacho, now i turned off idle control valve, but this problem couses from idle control valve or used new ecu?
Does the 6cyl W126 (280SE/L) have an equivalent part & if so is it located up next to the steering column on a right hand drive?
can you post video on how to remove ICV from 1983 380sl
My 1990 560SEL 126 has a constant surging idle that no mechanic in my area has been able to fix its very sad it use to surge for 5-10 min. On startup then I could drive it but the last mechanic reset something and now surge doesn't go away could it be the module or the valve or a vacuum leak? I've given up on it
Tony Light 🤦♂️...so many guesswork mechanics out there trying to fidget with these cars when it’s just aging electronics that can be rebuilt with a soldering iron and Mouser catalog. I hope they didn’t take you to the cleaners while learning on your car...
@@fsb1284 yeah they did and its been in the garage for 5 years now
Tony Light that’s a shame...
Hello, +Tony Light and thank YOU so much for your question(s), we want to answer you as quickly as possible.
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Tony, please email me at mbownersforlife@bellsouth.net. I would like to know more about the issue and how it came about.
Can you tell me where it is located on a 1991 500sl. Thank you
I have a european w126 380sel and im experiencing high idle plus the abs light. What are my chances finding a replacement or should i try and repair it? Sometimes i get idle as high as 1.7k rpm and its really annoying especially when coming to a stop. Thank you
you likely need an overvoltage protection relay, and that's all. it is located in the fusebox.
Mercedes Classics with Pierre Hedary i did replace the overvoltage relay plus the idle control module and it didnt change amything, the abs light is still on. Also the idle control valve has 2 wires one of them connected to the body and the other one goes to the bottom left corner fuse. What am i missing here ?Im really bummed what else can i try?
Hi Pierre, I own a '89 560 SEL and I had this problem for years now and no local mechanic have being able to help me and the local Mercedes dealer's suggestion is for me to buy a new car, me my car idle rough ever since I change the fuel pumps because one of them was leaking, I tried everything, change spark plugs and wires, change the fuel filter, fuel distributor, change the idle control, and I just ran out of ideas because the repairs manuals that I have are just not helping.
Jaime, can you email at mbownersforlife@bellsouth.net? maybe i can help you. Did you adjust the 3mm allen screw?
Pierre I am considering buying a 1984 1 owner from the owner a 1984 300sd turbo would this car have this idle control issue . It only has 30995 miles. And what would be a fair price to offer her always stored inside but not driven in several years. I enjoy your channel very much. Robert here from op ks
no, it's all mechanical...the only thing that can go wrong on it is the rack damper pin. if the car is solid, you can't go wrong
Thanks Pierre I am going to see car next week looking forward to seeing a 300sd with only 30 thousand miles
Have you ever seen bad capacitors cause a low idle? Or do they mostly cause surges?
no, they almost always cause outright failure of the unit with high idle speed. Low idle is usually related to the fuel system being over pressurized. Extremely high control pressures choke the air flap.
Mercedes Classic with Pierre Hedary I’ll have to pull my CIS gauge out then...
Do w123 280e have these as well ?
goated
I have an issue with my 1984 500 SEC Euro market car that misfires upon startup, then after about 5 seconds of running it smooths out and isles at 550 RPM when cold. Then, as the engine warms up, the idle rises and usually stops rising at around 1500 RPM but occasionally can be as high as 2000 RPM. I suspect that the high idle is idle control related. I assume that the misfire upon startup is related to a different issue. I’m hoping that the misfire issue will be solved by replacing parts that I was intending to replace anyway due to the car’s age and it’s higher mileage. What are your thoughts?
Hello, +Spencer Tarter and thank YOU so much for your question(s), we want to answer you as quickly as possible.
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Spencer, 2 things. the high idle is likely the idle control unit. the difficult start/miss might be a bad fuel pressure accumulator, or , possibly several injectors that are bleeding off.
Where is the module? I've looked in the passenger footwell and the engine bay but don't see anything
Hello, hamshank29 and thank YOU so much for your question(s), we want to answer you as quickly as possible.
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@@mercedesclassicswithpierre1753 Seriously? And you accuse mercedes source of being after peoples money 🤣
How many folks have had their cars made worse by mechanics trying to fix an electrical problem with a mechanical solution? Thankfully, my dealership has a 35 year veteran Benz tech. who lights up when he sees my A124 pull in the garage. These cars are different than the new ones and the number of people qualified to touch them without “making the patient worse” is dwindling 😢
I agree. glad you have competent service for your 124! what year and model is it>?
Mercedes Classic with Pierre Hedary 1995 E320...late assembly for a 1995, too.
@@fsb1284 where is your dealer
Faiz Rahman Loc at: www.mercedesabq.com/about-us/staff/
is this plug and play? or it needs to be programmed by a professional mechanic. Thank you
plug and play...no "programming" needed..."programming" was not a thing then.
Mercedes Classic with Pierre Hedary thank you, and best of all no tools needed, car idles much better now.
I do enjoy your videos! However I wish you would show more hands on repair. I also like how your hands are never clean like mine! How bout that Kent with his french manicured nails though? Or are they lee press-on
kent has his green gloves
i dont have issue with a mechanic wearing gloves..u need to protect your money maker. Plus no one wants dirty hands in a car...great video tho
Please tell me specifically which repairs you would like to see and i will incorporate them in the future. We make these based on viewer request.
That’s so funny!! 😄 🤣
I learned a long time ago never to trust a mechanic with clean hands.
I have 420sel can I repair mine control unit
1990 420sel idle control unit plz need help
Saleem, are you getting an ABS light? what is your idle speed. the best way to reach is via email at mbownersforlife@bellsouth.net
one does not simply, escape electronic failures
Have no idea what this guy is talking about