Some scan tools allow you bi- directional control of the HPFP , these Mazda pumps are notorious for failure. You can see that the requested pressue was not met , extended crank and fuel trim show the rest of the picture of low fuel pressure .
@SMiller-q7c yes my autel and snap on triton do it not sure it this mazda had the function?! if the customer has us out for the repair then ill double check!
One other thing to check is if you have scan data on duty cycle to the HPFP control solenoid, if it shows 100% duty cycle you know the PCM is trying to overcome a low fuel pressure issue. It's PWM OR duty cycle controlled
I'm with the pump. PCM command is there, and it reads the pressure. No low circuit code for the pump... not foolproof, but does suggest good electrical connection.
So would it be a good idea to also check the low side fuel pump? I'm thinking that low pressure in could also be lower pressure out. If you have a low side Schrader valve, that would be a quick check. If I'm not mistaken, there was a TSB on certain Mazdas for faulty high pressure fuel pumps. Not sure this would apply to your situation. Thanks for posting this one! Looks like you're doing a great job out there!
@bobcombs7138 thanks for watching!!!! there wasn't a valve for it. But fuel test my kit i could tap into the line to test . but id say you have trust your diagnosis. From the data i have the pressure sensor is good which shows 60-80 psi. spec said that key on engine off that that was good. And it ran and drove. I believe if im not wrong that if the main pump in the tank was bad it wouldnt run at all. the high pressure cant pull fuel from the tank. And yes there is a known issue with these pumps.
Definitely seems like a bad high pressure fuel pump. I don't remember on Mazda if the pressure should go full high or low with the pump disconnected. I know gm goes full pressure and Honda goes to no pressure. It would be interesting to know what this Mazda defaults to. The bag is a life saver, feel free to take any ideas 😀
@@3TsMOBILEAUTOMOTIVEREPAIR Yes, after you fix it, I would appreciate it if you could unplug it again to check which default it is to. Just for science.
@romeoholder4453 Yes we did there is a follow up video Part two Mazda CX5 | Also confused customer called said he had a Hyundai CRV | ua-cam.com/video/mQ6MAe4cp1I/v-deo.html
![The ULTIMATE Air Filter Test [Engineer Tested]](http://i.ytimg.com/vi/RdbFAG5xbyY/mqdefault.jpg)
Some scan tools allow you bi- directional control of the HPFP , these Mazda pumps are notorious for failure. You can see that the requested pressue was not met , extended crank and fuel trim show the rest of the picture of low fuel pressure .
@SMiller-q7c
yes my autel and snap on triton do it not sure it this mazda had the function?! if the customer has us out for the repair then ill double check!
One other thing to check is if you have scan data on duty cycle to the HPFP control solenoid, if it shows 100% duty cycle you know the PCM is trying to overcome a low fuel pressure issue. It's PWM OR duty cycle controlled
You know i dont know if i saw a duty cycle. I double check that also if we get the job for repair
@@3TsMOBILEAUTOMOTIVEREPAIRyeah it was there I saw when you were searching fuel trims the duty cycle was at 95%
I'm with the pump. PCM command is there, and it reads the pressure. No low circuit code for the pump... not foolproof, but does suggest good electrical connection.
So would it be a good idea to also check the low side fuel pump? I'm thinking that low pressure in could also be lower pressure out. If you have a low side Schrader valve, that would be a quick check. If I'm not mistaken, there was a TSB on certain Mazdas for faulty high pressure fuel pumps. Not sure this would apply to your situation.
Thanks for posting this one! Looks like you're doing a great job out there!
@bobcombs7138
thanks for watching!!!!
there wasn't a valve for it. But fuel test my kit i could tap into the line to test . but id say you have trust your diagnosis. From the data i have the pressure sensor is good which shows 60-80 psi. spec said that key on engine off that that was good. And it ran and drove. I believe if im not wrong that if the main pump in the tank was bad it wouldnt run at all. the high pressure cant pull fuel from the tank. And yes there is a known issue with these pumps.
Definitely seems like a bad high pressure fuel pump. I don't remember on Mazda if the pressure should go full high or low with the pump disconnected. I know gm goes full pressure and Honda goes to no pressure. It would be interesting to know what this Mazda defaults to. The bag is a life saver, feel free to take any ideas 😀
@advancedleveldiagnostics
I unplugged the spill valve with no change. I assume thats what you mean?
@@3TsMOBILEAUTOMOTIVEREPAIR Yes, after you fix it, I would appreciate it if you could unplug it again to check which default it is to. Just for science.
@advancedleveldiagnostics
Yeah, of course if they go through with the repair, I’ll definitely do that and let you guys know
Did you ever got the issue solved?
@romeoholder4453
Yes we did there is a follow up video
Part two Mazda CX5 | Also confused customer called said he had a Hyundai CRV |
ua-cam.com/video/mQ6MAe4cp1I/v-deo.html
Wow. Rural
Yea mostly dirt roads here every where
Good diag Ben.
Thank you
AllData is the best ?
No bung on fuel rail for a guage?
No its high pressure. idle is over 400psi. It can get to over 1500 psi when they run correctly.
so far haven't had to work on only 1 with direct injection