P0300 nightmare
#22
Are you talking about the fuel trims?
I'm assuming that 25 & 50 are REAL high?
Which means since I already checked the pressure, I should pull the injectors and have them bench checked?
I'm assuming that 25 & 50 are REAL high?
Which means since I already checked the pressure, I should pull the injectors and have them bench checked?
#23
With positive fuel trims, the fuel mixture is too lean, (too much air, or not enough fuel). You checked pressure and came up with 58psi at the service port, which is too low, and will cause a lean condition. Without checking fuel pressure and leakdown at the fuel filter, as explained in the link I posted, the 58psi basically tells us the pump is running, that's it. Kinda like going to the doctor and tell him your temperature is fine, but you're gut hurts. Need to do more testing. Post all 4 readings from the link.
#24
Thanks I'll have to take a wack at it tomorrow, to be honest I'm a little iffy when it comes to fuel injection and fuel systems, these are kinda new to me, I'm used to fuel pump on the side of the block and a carb. So I was hoping to avoid the fuel systems, oh well I'll never learn if I don't try
#25
With positive fuel trims, the fuel mixture is too lean, (too much air, or not enough fuel). You checked pressure and came up with 58psi at the service port, which is too low, and will cause a lean condition. Without checking fuel pressure and leakdown at the fuel filter, as explained in the link I posted, the 58psi basically tells us the pump is running, that's it. Kinda like going to the doctor and tell him your temperature is fine, but you're gut hurts. Need to do more testing. Post all 4 readings from the link.
I did follow the instructions in my MOTOR manual and my Chilton's manual.
with my fuel pressure gauge.
I checked the pressure at the filter; had to pull the fuel filter and insert a "T" junction and test the pressure; with the ignition on, engine off and with the engine on.
I checked the pressure at the service port with the ignition on, engine off and with the engine on.
Both manuals said the pressure should be between 60-66 PSI with the engine off and drop 3-10 PSI with the engine running.
I got 62 PSI withe ignition on, engine off and 56 with the engine on.
Readings were the same at both test locations.
#26
Toss them in the trash. They have incomplete, incorrect, and totally worthless information, as you just found out. You're spinning your wheels and getting nowhere, fast. Read the article in post #4, and follow the directions. THAT is the correct way to check & diagnose the system. Then post all 4 readings.
#27
OK so the reading at the service port are 62/56
the fuel pump max readings are around 88/56
I finally broke down and got the A/C Delco cap & rotor, P0300 went away, drove around the block a few times and it drives fine when I accelerate slow and steady, but I put my foot into it and it pops back; and the freeze data still shows high fuel trims.
Does that mean my fuel injectors are screwed?
Could this all mean I need to replace the fuel injectors?
http://www.rockauto.com/catalog/more...id=509&jpid=12
the fuel pump max readings are around 88/56
I finally broke down and got the A/C Delco cap & rotor, P0300 went away, drove around the block a few times and it drives fine when I accelerate slow and steady, but I put my foot into it and it pops back; and the freeze data still shows high fuel trims.
Does that mean my fuel injectors are screwed?
Could this all mean I need to replace the fuel injectors?
http://www.rockauto.com/catalog/more...id=509&jpid=12
Last edited by FUN-V; 10-15-2015 at 01:09 PM.
#28
Using AC Delco ignition parts, does make a difference. Fuel pressure regulator is fine. There are no leaks in the fuel delivery system, and the pump is fine. Without studying fuel trims during the "pop back", there is nothing pointing to faulty injectors. So before throwing money at it, possibly needlessly, I would have camshaft retard checked, and adjusted if necessary. Might not be a bad idea to have them perform the crankshaft position sensor relearn at the same time.
#30
Camshaft retard is checked using a capable scan tool. Lesmyer has a set up for android that works. The elcheapo scan tools will not access the data stream. Post the freeze frame data, if you have it. They might help.