Even my 300SL-24 with M104 engine had the same problem. My mechanic had replaced all the spark plugs, fuel injectors etc. Nothing helped. I had a friend told me to change the distributor and it worked. The moisture comes from the camshaft. If that happens again, you need to change the camshaft seal as well.
This is unbelievable. I have exactly the same car and exactly the same problem and was going to look at everything you looked at first 😂 It’s like a miracle that I just came across your video! Thank you so much for posting, you’ve saved me a lot of time and money
Thank you mate, the reason why I made the video was my frustration not being able to diagnose the issue for a long time. Just didn't want every one else to suffer. Please Subscribe for more videos :)
Hi My Friends, please watch the first 6-7 minutes of the video if you own an old mercedes like me. It will help you to diagnose your M119 Engine, whether you have a W140, W124, C140, R129 or W210, also I have included the test drive and acceleration at the end of the video. Thanks for subscribing, liking sharing, feel free to ask questions here, I will try to answer ASAP. Cheers.
the hard start when the engine is hot is the CAMSHAFT position sensor....you said CRANKSHAFT in the video ( the crankshaft sensor issue would be a different problem : for instance, stalling when engine is hot) I actually replaced my camshaft position sensor last year ( 2022) when the engine was taking longer to start when warm/hot and and some acceleration issues the first couple of minutes after starting it. As for the distributor caps, I know I have to change them when the car starts to misfire when the engine is getting at temperature...When the engine is at temperature and driving for a few minutes, then the misfire will disappears ( at least, it does on my W124 400E) i usually change them every 50K miles ( this is when they usually start to misfire on my car)... My 1993 W124 400E has 350K miles on it ( I daily drive it in the USA)
I have a green 93’ 400e with the same symptoms I’m gonna do the dizzy caps, both crank/cam sensors and plugs if that doesn’t work then my harness might be junk
Hey I have a similar problem with my sl 300 r129. At first the car starts completely normal bit when you start driving it for a bot and stop the engine or sit at a red light a little longer the when i try to normally drive away the rpm drops and the car almost shuts off. And when i stop the motor and start it it goes off sometimes. When i manage to rev the car to about 4000 rpm when it makes problems ist goes away for a while. I changed the distributor cap the injektors and the cables which connect the distribuor whith the injektors. What else could the problem be?
1993/3, the cables are all good as far as I checked them myself. I noticed that when I wiggle the MAS the rpm go crazy I think it has something to do with that
@mehmetakifayyildiz4695 still 93/3 can be the biodegradable wiring looms issue, my W124 is 93/3 built and biodegradable... check the throttle body harness too.
Nice job! You have some beautiful roads and scenery around! I have a manual swapped M119 W124 on my channel if you're interested. I have also been trouble shooting similar things as of late but finally have it running right again. Appreciate the content, sub'd!
I would never have guessed the distributors were at fault, specially after seeing how well ran when cold. I guess there was condensation inside the cap and when heats up, that created a humid environment where the spark could jump anywhere
The moisture problem and the black color of the contacts in the distributor cap is caused by moisture and oil vapor leaking past the seal behind the rotor to the distributor cap. A new distributor cap will be a temporary solution. Sooner or later you will have problems again. The solution is to place a 2nd seal behind the rotor around the camshaft. So 1 old seal out and 2 new seals in succession. This on both sides of course. Since I did it I've been driving 90,000 km without any problems. This is the only correct solution. I'm happy to answer questions if you want to do it too.
The cause of the problem with the distributor is the seal behind the rotor. This seal leaks oil vapor and water from the engine to the distributor. The solution is simple and cheap. There is originally only 1 seal, but there is room to place 2 seals behind each other. I have now driven them 100k without any problem with the distributor. These are still spotless. I did install a Beru distributor and rotor. Is slightly better than Bosch..
I'm glad to see your video. My car has a similar problem with your car. If I leave it parked for a day or two, when I come back to start the engine it looks fine and runs fine. But when the engine starts to heat up So a vibration occurs. Looking at the engine, I can saw the engine shaking. And when the car was parked for an hour or two, the vibrations disappeared and driving was normal. If I drive every day, there will be no symptoms like this. Does your car after replacing the distributor cap and being parked for several days still vibrates? Please update with me.Thank you so much.
It is all fixed now, it was all the distributor caps my friend :) inspect yours, if they are older than 50000 km, they will need replacing... enjoy your mercedes
@@BenzAddiction I'll try to find replacement parts. I searched for the cause of the vibration for a long time. I hope it will bring my car back to normal as well as your car. Thanks.
Hello, the change of distributor cap solved the hard warm start up also? I have the same problems, but sometimes when i want to start the warm engine, they backfire into exhaust and not start. After a few minutes it turns on.
Hi mate, I had the warm start up problem but it was more like a over cranking issue, the engine would start on the second start. I had no back firing issue.
Hey BA, I changed the caps, rotors, rotor brackets and cleaned the dust shield. The seal looked fine so I continued using it but the issue is still here. It feels like a dead cylinder (or more) and the idle is steady at like 500, but it’s vibrating the entire car. A huge piece of info is that one of the red plastic plug puller things was shattered, and it didn’t take much force to remove the wire from the plug, but every other plug wire required a decent amount of effort to get out. Could this be the source of the issue? I don’t remember how the plug wires looked when I inspected them, but they didn’t look too terrible, maybe a small amount of white stuff on the inside. Also, the wires are MB branded, and everyone I’ve seen doesn’t have mb branded wires. Could these be oe? I just got the car in April, so I’m not sure about maintenance. All I know is that the wiring harnesses were replaced, but it looks like everything else is oe.
Obviously this happens when the car gets warm, next time quickly pull out one of the caps right after and check for condensation. If so, replace the seals...
Thank you for this insight into my 1991 R129 maintenance - as I’m also starting to experience similar fluctuations in throttle response actions. Bless you & thanks again - Mark (USA)
@@BenzAddiction I already have been subscribed for some time as I enjoy watching/learning what your discovering in your personal journey with your R129! Your discoveries actually SAVE me time & money at my end - especially when here at my end labor costs at my MB Maintenance/ Dealership is: $195.00 (USD) an hour. Learning through your videos actually save me hundreds of dollars - so thank you - PLUS I enjoy your instructional videos. To be 70+ degrees & 😎 sunny here today (outside Indianapolis) (finally) so plan on bringing my R129/AMG out of the garage for a nice drive. Though in short order since it was stored during winter months a full maintenance I will be doing on her. My ‘91 R129 is Schwarz Black with Palomino Interior w/ 104,000 miles on her. Runs strong but the 32 year old plastic pieces around the vehicle are having to be replaced (one by one) as I’m sure your running into also. It’s a journey into learning all about my machines life and though the pieces are expensive - it’s so satisfying when old plastic is replaced with new! Thanks again for the time you’ve spent to share your R129 journey with us! Again, your saving me $$$ and I am very grateful for this. God bless & stay safe - Mark🙏
I have a cold start (small) issue on my 93 M119 SL R129. It revs up to 1100rpm or so then goes back to normal 600-700rpm after starting it up. Does this 3times before the constant and normal idle(600-700rpm)comes, so basically after the cold start it takes 10sec until everything is all right and just fine but I don't understand why my car started to do this.
Change the seal behind the rotor. Thats the probleem. There is 1 seal original but there is space to place 2 seals. The moister and olie vapour from the engine can not to the distriburcap. A new cap and rotor are not the solution.. 👍
There is an ideal summary of this issue on the W124 E500/500E board. Distributor cap insulation is *usually* the cause of uneven idle/hesitation which only occurs when engine has warmed. People report different and inconsistent results depending on the brand used.
The reason that moisture and oil vapor enter the distributor cap is that the sealing ring behind the rotor of the camshaft is bad. Oil vapor is leaking down to the distributor cap. There is a simple and cheap solution. Originally there is 1 seal but there is room to mount 2 seals behind each other. The seal costs 15.00 euros at the dealer. I have already driven 90,000 km and there is no moisture and oil vapor in it at all. A new distributor cap and rotor is a temporary solution, moisture and oil vapor will return anyway. I also have pictures of it..
I have the same problem and when I want to start the warm engine, they shoot into the exhaust and into the intake pipe, did you have that problem too? thanks
Even my 300SL-24 with M104 engine had the same problem. My mechanic had replaced all the spark plugs, fuel injectors etc. Nothing helped. I had a friend told me to change the distributor and it worked. The moisture comes from the camshaft. If that happens again, you need to change the camshaft seal as well.
Very true 👍
This is unbelievable. I have exactly the same car and exactly the same problem and was going to look at everything you looked at first 😂 It’s like a miracle that I just came across your video! Thank you so much for posting, you’ve saved me a lot of time and money
Thank you mate, the reason why I made the video was my frustration not being able to diagnose the issue for a long time. Just didn't want every one else to suffer. Please Subscribe for more videos :)
Hi My Friends, please watch the first 6-7 minutes of the video if you own an old mercedes like me. It will help you to diagnose your M119 Engine, whether you have a W140, W124, C140, R129 or W210, also I have included the test drive and acceleration at the end of the video. Thanks for subscribing, liking sharing, feel free to ask questions here, I will try to answer ASAP. Cheers.
the hard start when the engine is hot is the CAMSHAFT position sensor....you said CRANKSHAFT in the video ( the crankshaft sensor issue would be a different problem : for instance, stalling when engine is hot)
I actually replaced my camshaft position sensor last year ( 2022) when the engine was taking longer to start when warm/hot and and some acceleration issues the first couple of minutes after starting it.
As for the distributor caps, I know I have to change them when the car starts to misfire when the engine is getting at temperature...When the engine is at temperature and driving for a few minutes, then the misfire will disappears ( at least, it does on my W124 400E)
i usually change them every 50K miles ( this is when they usually start to misfire on my car)...
My 1993 W124 400E has 350K miles on it ( I daily drive it in the USA)
👍
I have a green 93’ 400e with the same symptoms I’m gonna do the dizzy caps, both crank/cam sensors and plugs if that doesn’t work then my harness might be junk
@@codyturner9402 My car is still healthy after replacing the caps.
Hey I have a similar problem with my sl 300 r129. At first the car starts completely normal bit when you start driving it for a bot and stop the engine or sit at a red light a little longer the when i try to normally drive away the rpm drops and the car almost shuts off. And when i stop the motor and start it it goes off sometimes. When i manage to rev the car to about 4000 rpm when it makes problems ist goes away for a while. I changed the distributor cap the injektors and the cables which connect the distribuor whith the injektors. What else could the problem be?
What year is this? What is the condition of the woring harness?
1993/3, the cables are all good as far as I checked them myself. I noticed that when I wiggle the MAS the rpm go crazy I think it has something to do with that
@mehmetakifayyildiz4695 still 93/3 can be the biodegradable wiring looms issue, my W124 is 93/3 built and biodegradable... check the throttle body harness too.
@@BenzAddiction I will thanks
Nice job! You have some beautiful roads and scenery around! I have a manual swapped M119 W124 on my channel if you're interested. I have also been trouble shooting similar things as of late but finally have it running right again. Appreciate the content, sub'd!
Thank you my friend, I will definitely check your videos and channel out as I love W124 too.
I would never have guessed the distributors were at fault, specially after seeing how well ran when cold.
I guess there was condensation inside the cap and when heats up, that created a humid environment where the spark could jump anywhere
Yes, but I cleaned the old caps few times and it did make no difference to the post warm-up running...
The moisture problem and the black color of the contacts in the distributor cap is caused by moisture and oil vapor leaking past the seal behind the rotor to the distributor cap. A new distributor cap will be a temporary solution. Sooner or later you will have problems again. The solution is to place a 2nd seal behind the rotor around the camshaft. So 1 old seal out and 2 new seals in succession. This on both sides of course. Since I did it I've been driving 90,000 km without any problems. This is the only correct solution. I'm happy to answer questions if you want to do it too.
You are definitely correct. I will do this soon. Thank you.
Can you give part number for seal please 🙏
Any ASR problems? Wiring harness?
Wiring harness is brand new,
The cause of the problem with the distributor is the seal behind the rotor. This seal leaks oil vapor and water from the engine to the distributor. The solution is simple and cheap. There is originally only 1 seal, but there is room to place 2 seals behind each other. I have now driven them 100k without any problem with the distributor. These are still spotless. I did install a Beru distributor and rotor. Is slightly better than Bosch..
Thank you for sharing this with everyone, I am sure it will be helpful to many people...
I'm glad to see your video. My car has a similar problem with your car. If I leave it parked for a day or two, when I come back to start the engine it looks fine and runs fine. But when the engine starts to heat up So a vibration occurs. Looking at the engine, I can saw the engine shaking. And when the car was parked for an hour or two, the vibrations disappeared and driving was normal. If I drive every day, there will be no symptoms like this. Does your car after replacing the distributor cap and being parked for several days still vibrates? Please update with me.Thank you so much.
It is all fixed now, it was all the distributor caps my friend :) inspect yours, if they are older than 50000 km, they will need replacing... enjoy your mercedes
@@BenzAddiction
I'll try to find replacement parts. I searched for the cause of the vibration for a long time. I hope it will bring my car back to normal as well as your car. Thanks.
@user-uf4cy9bn8c I am sure you will soon, keep us posted.
Did you ever fix this problem ? What was wrong ?
@@henboy1 fixed the hesitation and rough warm idle issue...
forgot to add : also change your insulators ( the orange "cups") located behind the distributor rotors!!! ( as they will also let moisture in!)
👍
Great video. Thx for sharing
Thanks for watching and subscribing 👍
Hello, the change of distributor cap solved the hard warm start up also? I have the same problems, but sometimes when i want to start the warm engine, they backfire into exhaust and not start. After a few minutes it turns on.
Hi mate, I had the warm start up problem but it was more like a over cranking issue, the engine would start on the second start. I had no back firing issue.
ARS
👍
Now I want to replace my distributor caps. Listening to your before change engine sound is the exact same sound mine is making.
Yes, my problem is solved but if you can replace your distributor seals too.
Nice. Glad you fixed it. The car sound amazing after you fixed it.
Thanks mate :)
Same problem, i replaces the distributor caps and it didnt solve the problem.. spark plugs are next
If it happens again, distributors seal would be next, I am preparing the ingredients for that too.
@@BenzAddiction do you have a link for the seals? I cant seem to find them
Hey BA, I changed the caps, rotors, rotor brackets and cleaned the dust shield. The seal looked fine so I continued using it but the issue is still here. It feels like a dead cylinder (or more) and the idle is steady at like 500, but it’s vibrating the entire car. A huge piece of info is that one of the red plastic plug puller things was shattered, and it didn’t take much force to remove the wire from the plug, but every other plug wire required a decent amount of effort to get out. Could this be the source of the issue? I don’t remember how the plug wires looked when I inspected them, but they didn’t look too terrible, maybe a small amount of white stuff on the inside. Also, the wires are MB branded, and everyone I’ve seen doesn’t have mb branded wires. Could these be oe? I just got the car in April, so I’m not sure about maintenance. All I know is that the wiring harnesses were replaced, but it looks like everything else is oe.
Even the caps and rotors looked oe.
Obviously this happens when the car gets warm, next time quickly pull out one of the caps right after and check for condensation. If so, replace the seals...
@@BenzAddiction the thing is, is that it happens cold and warm
@@avlvelo2688 might have other reasons then...
Thank you for this insight into my 1991 R129 maintenance - as I’m also starting to experience similar fluctuations in throttle response actions. Bless you & thanks again - Mark (USA)
Hi Mark, thank you for the positive feedback and if you like, please subscribe as more videos coming.
@@BenzAddiction I already have been subscribed for some time as I enjoy watching/learning what your discovering in your personal journey with your R129! Your discoveries actually SAVE me time & money at my end - especially when here at my end labor costs at my MB Maintenance/ Dealership is: $195.00 (USD) an hour. Learning through your videos actually save me hundreds of dollars - so thank you - PLUS I enjoy your instructional videos. To be 70+ degrees & 😎 sunny here today (outside Indianapolis) (finally) so plan on bringing my R129/AMG out of the garage for a nice drive. Though in short order since it was stored during winter months a full maintenance I will be doing on her. My ‘91 R129 is Schwarz Black with Palomino Interior w/ 104,000 miles on her. Runs strong but the 32 year old plastic pieces around the vehicle are having to be replaced (one by one) as I’m sure your running into also. It’s a journey into learning all about my machines life and though the pieces are expensive - it’s so satisfying when old plastic is replaced with new! Thanks again for the time you’ve spent to share your R129 journey with us! Again, your saving me $$$ and I am very grateful for this. God bless & stay safe - Mark🙏
If any one wil information about the solution i can send picture by mail of the 2 seals..
Thanks Marcel :)
Part number on rotor seal?
Я уверен ваша проблема появилась вновь если да то ответьте мне
No.
I have changed them and the problem came back again, how does your work now?
Did you replace the distributor seals too?
@@BenzAddiction Yes, the rubber rings on the inside.
You need to change the seal of the camshaft too.
I have a cold start (small) issue on my 93 M119 SL R129. It revs up to 1100rpm or so then goes back to normal 600-700rpm after starting it up. Does this 3times before the constant and normal idle(600-700rpm)comes, so basically after the cold start it takes 10sec until everything is all right and just fine but I don't understand why my car started to do this.
I would say check your fuel pressure first...
Did you find out what the problem is?
Hello, One more question. You change only the distributor cap or change both distributor and rotor?
I only replaced the caps.
Change the seal behind the rotor. Thats the probleem. There is 1 seal original but there is space to place 2 seals. The moister and olie vapour from the engine can not to the distriburcap. A new cap and rotor are not the solution.. 👍
I have picture of the operationele..
@Marcel b if you can upload it somewhere, please leave the link here so everyone can see and use. Cheers
@@BenzAddiction yes, i try
Nice 👍 work
Thanks mate.
There is an ideal summary of this issue on the W124 E500/500E board. Distributor cap insulation is *usually* the cause of uneven idle/hesitation which only occurs when engine has warmed. People report different and inconsistent results depending on the brand used.
Thanks for sharing my friend
The reason that moisture and oil vapor enter the distributor cap is that the sealing ring behind the rotor of the camshaft is bad. Oil vapor is leaking down to the distributor cap. There is a simple and cheap solution. Originally there is 1 seal but there is room to mount 2 seals behind each other. The seal costs 15.00 euros at the dealer. I have already driven 90,000 km and there is no moisture and oil vapor in it at all. A new distributor cap and rotor is a temporary solution, moisture and oil vapor will return anyway. I also have pictures of it..
I have the same problem and when I want to start the warm engine, they shoot into the exhaust and into the intake pipe, did you have that problem too? thanks
Hi mate, warm start up up was harder but no back firing sound in the intake or exhaust...
@@BenzAddiction thanks for.
Did you solved the problem?
@mendigo As far as I remember, the engine once started on the second cracking, but that's maybe because I limit each cracking to 3 seconds.