HiHoeSilver
Away!
Ha! I figured that's why you wrote it twice. I edited mine to be clear. Key on engine off will prove to be the important one in this case, i think. We know the thing runs.
Starting issue
- Thread starter dross99_si
- Start date
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Ha! I figured that's why you wrote it twice. I edited mine to be clear. Key on engine off will prove to be the important one in this case, i think. We know the thing runs.
OP
OP
dross99_si
Full Access Member
So can all this fuel pressure testing simply be done with something like the Tech-2, or do I HAVE to have a pressure gauge connected to the rail?
iamdub
Full Access Member
Gonna need a mechanical gauge hooked to the rail. The PCM reports fuel pressure in the live data stream, but I don't think this is from an actual pressure transducer. It's probably calculated based off an algorithm using input from other sensors. You want an "unbiased, third-party" input in this scenario.
Yes, get as much fuel out of the tank as possible. I had a handheld hand pump that I cranked, till I got an electric one, that had a hose pushed in to the tank and out to gas cans and drained it as dry as I could. Elevation is a good thing and proper toll set. Pay very close attention to all that surrounds the tank and what is on top and if you come to a stopping point with uncertainty of something, get on here and ask and supply pics if possible. In another thread there is a guy that did a fuel pump replacement and when he put it all back together he pinched a vent line and that caused a code on restart. I am very OCD and when I did tanks and pumps I tied everything back as I disconnected so that I could then pull back in to the tank area as needed.
OP
OP
dross99_si
Full Access Member
Have any of you guys installed a permanent pressure gauge on the rail?
OP
OP
dross99_si
Full Access Member
Update:
Yesterday swathdiver (James) was nice enough to come over with the Tech 2 to see if we could figure out the P0442 and check fuel pressure to diagnose the starting issue. Unfortunately the fuel system monitoring was not an option listed for my particular vehicle. Not sure if the 2007s support this or not..
On a better note we did some experimenting with the EVAP purge valve. With the engine running, the vent valve closed and the purge valve commanded open (even to 100%) there was never a negative pressure generated in the fuel tank according to the fuel tank pressure sensor. In other words the new purge valve I purchased and installed a while back had to be defective.
The purge valve is a Duralast lifetime part from AutoZone. This was against my better judgement as I usually only purchase OEM replacement parts. This is exactly why.
After James left yesterday afternoon I hopped on Amazon and ordered a Genuine GM EVAP purge valve.
This afternoon the new part arrived and I installed it. The Duralast part was definitely defective because I am able to suck through it with ease. No resistance at all.
Now we wait and see if the code comes back and/or the starting issue persists.
Thanks to all who have been helping me with this
Yesterday swathdiver (James) was nice enough to come over with the Tech 2 to see if we could figure out the P0442 and check fuel pressure to diagnose the starting issue. Unfortunately the fuel system monitoring was not an option listed for my particular vehicle. Not sure if the 2007s support this or not..
On a better note we did some experimenting with the EVAP purge valve. With the engine running, the vent valve closed and the purge valve commanded open (even to 100%) there was never a negative pressure generated in the fuel tank according to the fuel tank pressure sensor. In other words the new purge valve I purchased and installed a while back had to be defective.
The purge valve is a Duralast lifetime part from AutoZone. This was against my better judgement as I usually only purchase OEM replacement parts. This is exactly why.
After James left yesterday afternoon I hopped on Amazon and ordered a Genuine GM EVAP purge valve.
This afternoon the new part arrived and I installed it. The Duralast part was definitely defective because I am able to suck through it with ease. No resistance at all.
Now we wait and see if the code comes back and/or the starting issue persists.
Thanks to all who have been helping me with this
Tell the truth, @dross99_si, one of @swathdiver's kids did the work, right? LOL
wjburken
Supporting Member
TYF Collaboration FTW!Update:
Yesterday swathdiver (James) was nice enough to come over with the Tech 2 to see if we could figure out the P0442 and check fuel pressure to diagnose the starting issue. Unfortunately the fuel system monitoring was not an option listed for my particular vehicle. Not sure if the 2007s support this or not..
On a better note we did some experimenting with the EVAP purge valve. With the engine running, the vent valve closed and the purge valve commanded open (even to 100%) there was never a negative pressure generated in the fuel tank according to the fuel tank pressure sensor. In other words the new purge valve I purchased and installed a while back had to be defective.
The purge valve is a Duralast lifetime part from AutoZone. This was against my better judgement as I usually only purchase OEM replacement parts. This is exactly why.
After James left yesterday afternoon I hopped on Amazon and ordered a Genuine GM EVAP purge valve.
This afternoon the new part arrived and I installed it. The Duralast part was definitely defective because I am able to suck through it with ease. No resistance at all.
Now we wait and see if the code comes back and/or the starting issue persists.
Thanks to all who have been helping me with this
wjburken
Supporting Member
How else are they going to learn?
As a kid, my dad would tell me to go start the grill.
Then he would tell me to spread the coals out and put the meat on.
Then he would tell me to turn the meat.
Then he would tell me to take the meat off.
Then he would tell the neighbor that he grilled for supper.
I now know have a 13 year old son that I tell to go start the grill.......
How often do you tell that son to "Pull my finger"? 
