TrickPerformanceProducts NEW R&D truck
Just had a car come in with an off idle stumble... Was wrong plugs even though they were new and bad wires.... 
The codes show mis firing and commumications issues.
12-07-2008, 09:45 PM
#167
Oh my goodness.... Let see What we can try an fix....
P0300 is multi- random miss fire.... Probally old plugs and wires caused it. It's not on one specific cylinder so I would guess probally a crank sensor malfunction. When one coil dies or is going out you usually get a specific code on that cylinder. It Does show complete on the continuous test so try and clear them all from the history and see if it comes back.
P0140-P0160 basically say the O2 are not working... did you guys delete the rear ones or do something with the cats and for get to change that in the tune??? I believe you can turn the rear ones off with tuning soft ware other wise replace them.
P0405 is EGR recirculation valve Low voltage... Most likely the pin on the EGR valve is not making good contact in the conector.
on the P0748 EGR code that is most likely the Pressure sensor on the tank. I dont have any info in front of me on that. This could be a sign that The OEM Fuel pump assembly Is taking a crap... If your feul Level gauge is acting up Change the whole unit out... The pressure sensor unit is the black sensor on the top of the Pump assembly... It's not cheap by it self either... some tanks do not have it in the pump assembly, they were seprate in the rear on top of the tank...
hope this helps stear you in the right direction at least...
P0300 is multi- random miss fire.... Probally old plugs and wires caused it. It's not on one specific cylinder so I would guess probally a crank sensor malfunction. When one coil dies or is going out you usually get a specific code on that cylinder. It Does show complete on the continuous test so try and clear them all from the history and see if it comes back.
P0140-P0160 basically say the O2 are not working... did you guys delete the rear ones or do something with the cats and for get to change that in the tune??? I believe you can turn the rear ones off with tuning soft ware other wise replace them.
P0405 is EGR recirculation valve Low voltage... Most likely the pin on the EGR valve is not making good contact in the conector.
on the P0748 EGR code that is most likely the Pressure sensor on the tank. I dont have any info in front of me on that. This could be a sign that The OEM Fuel pump assembly Is taking a crap... If your feul Level gauge is acting up Change the whole unit out... The pressure sensor unit is the black sensor on the top of the Pump assembly... It's not cheap by it self either... some tanks do not have it in the pump assembly, they were seprate in the rear on top of the tank...
hope this helps stear you in the right direction at least...
12-08-2008, 06:42 AM
#168
Oh my goodness.... Let see What we can try an fix....
P0300 is multi- random miss fire.... Probally old plugs and wires caused it. It's not on one specific cylinder so I would guess probally a crank sensor malfunction. When one coil dies or is going out you usually get a specific code on that cylinder. It Does show complete on the continuous test so try and clear them all from the history and see if it comes back.
P0140-P0160 basically say the O2 are not working... did you guys delete the rear ones or do something with the cats and for get to change that in the tune??? I believe you can turn the rear ones off with tuning soft ware other wise replace them.
P0405 is EGR recirculation valve Low voltage... Most likely the pin on the EGR valve is not making good contact in the conector.
on the P0748 EGR code that is most likely the Pressure sensor on the tank. I dont have any info in front of me on that. This could be a sign that The OEM Fuel pump assembly Is taking a crap... If your feul Level gauge is acting up Change the whole unit out... The pressure sensor unit is the black sensor on the top of the Pump assembly... It's not cheap by it self either... some tanks do not have it in the pump assembly, they were seprate in the rear on top of the tank...
hope this helps stear you in the right direction at least...
P0300 is multi- random miss fire.... Probally old plugs and wires caused it. It's not on one specific cylinder so I would guess probally a crank sensor malfunction. When one coil dies or is going out you usually get a specific code on that cylinder. It Does show complete on the continuous test so try and clear them all from the history and see if it comes back.
P0140-P0160 basically say the O2 are not working... did you guys delete the rear ones or do something with the cats and for get to change that in the tune??? I believe you can turn the rear ones off with tuning soft ware other wise replace them.
P0405 is EGR recirculation valve Low voltage... Most likely the pin on the EGR valve is not making good contact in the conector.
on the P0748 EGR code that is most likely the Pressure sensor on the tank. I dont have any info in front of me on that. This could be a sign that The OEM Fuel pump assembly Is taking a crap... If your feul Level gauge is acting up Change the whole unit out... The pressure sensor unit is the black sensor on the top of the Pump assembly... It's not cheap by it self either... some tanks do not have it in the pump assembly, they were seprate in the rear on top of the tank...
hope this helps stear you in the right direction at least...
Thanks for the help, these code came before and after new plugs, new wires, different coil pack.
How do you test a crank sensor or do you just swap it out?
The truck runs and drives but has this feel like I have a dead hole or the timing is just off. I was thinking with this old of an engine, maybe the timing chain jumped a tooth?
Thanks for the help I will keep trying, let me know if you have any other ideas. If the truck ran with no hesitation I would not worry about some codes.
12-08-2008, 07:51 AM
#169
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I have had something similar happen to me in the past (clock reseting and comunication glitch) turned out I had the ground going to the fire-wall loose.
Double check all your positive and grounds.
Maybe worth a shot.
Double check all your positive and grounds.
Maybe worth a shot.
12-08-2008, 10:47 AM
#170
As mentioned Try the Main ground cable or cables. I also had a car were the terminal on the ground side was not making a good enough contact at the battery. I ended up having to cut it off and replace it. Solved all the comunication Issues we were having... Not sure what the comunication codes mean on yours.
Did you tune the ECU to turn off the rear O2's and the EGR??? Did the tune Stick???
As far as the motor being worn out. It probally is, but I have never seen a chain jump. They get lose, and the break but I Just don't see how it would be possible to Jump. I Don't think it could stretch that far with out something breaking. A belt on the other hand that's more likely...
I would try a few things first.
Make sure all electrical conections and vacume hoses are solid.
Like a compression check to make sure the cylinder and heads are sound. Not 100% sure but most likely on an early engine you have the composite head gaskets. With the lack of mateniance from the original owner and the boost it's possible on of them is leaking
Lets also check the fuel pressure...
Put a fuel gauge on the rail and see what the pressure is at idle. should be about 50 PSI. Then pull the Vacum line off the pressure regulatar and see if it goes up about 10 PSI.
With the vacum line ON, Rev the engine up to say 3 or 4 thousand rpm for a few seconds and see if the pressure drops below 45 PSI. Do it some what fast while its in park and hold it for like 5-10 seconds see what the pressure does...
Also Have you had the Injectors out??? did you change the injector size. did you ever change the fuel filter???
this should give you something to do...
Did you tune the ECU to turn off the rear O2's and the EGR??? Did the tune Stick???
As far as the motor being worn out. It probally is, but I have never seen a chain jump. They get lose, and the break but I Just don't see how it would be possible to Jump. I Don't think it could stretch that far with out something breaking. A belt on the other hand that's more likely...
I would try a few things first.
Make sure all electrical conections and vacume hoses are solid.
Like a compression check to make sure the cylinder and heads are sound. Not 100% sure but most likely on an early engine you have the composite head gaskets. With the lack of mateniance from the original owner and the boost it's possible on of them is leaking
Lets also check the fuel pressure...
Put a fuel gauge on the rail and see what the pressure is at idle. should be about 50 PSI. Then pull the Vacum line off the pressure regulatar and see if it goes up about 10 PSI.
With the vacum line ON, Rev the engine up to say 3 or 4 thousand rpm for a few seconds and see if the pressure drops below 45 PSI. Do it some what fast while its in park and hold it for like 5-10 seconds see what the pressure does...
Also Have you had the Injectors out??? did you change the injector size. did you ever change the fuel filter???
this should give you something to do...