TURNz
Full Access Member
- Joined
- Jan 30, 2012
- Posts
- 173
- Reaction score
- 28
It has been a while since I have been on. I got rid of my Tahoe a while back, but I am in need of some guidance to steer me in the right direction with my wife's 2004 Suburban Z71 Flex fuel (there are no FLEX fuel badges, but the VIN is FLEX and so is the fuel pump) ~250K mi.
This is going to be a long one, but bottom line is, had some things repaired and now we get P0171 and P0174 (bank 1 and 2 LEAN). Trying to troubleshoot it.
Here is the immediate back story of repairs.
The truck sat for almost a year. When we decided to get it on the road again, it blew a brake line. So took it to the mechanic and purchased the stainless brake line kit to replace them all.
He dropped the fuel tank to access the rear brake line, and ended up also replacing the fuel pump (housing was cracked).
We had been having EVAP issues prior to letting it sit, so I had him replace the charcoal cannister, evap purge solenoid and evap vent solenoid (dorman parts)
He also replaced two calipers and the rear u-joint on drive shaft (probably irrelevant, but)
When it's really cold, the idle will stumble until it warms up. If you put it in gear right away when it's cold, the check engine light flashes and you get "P0300". But once it's warm, that goes away. If I clear the LEAN codes and drive, they both go PENDING, and Bank 2 usually sets the code, and bank 1 stays PENDING.
What I've tried:
1. I used MAF cleaner on the MAF
2. I sprayed throttle-body cleaner on vacuum hoses while it's running, listening for a surge.
3. I check fuel pressure (40-45psi) primed with key on, engine off.
If it wasn't for the engine light, once it starts warming up, I wouldn't know anything was wrong. It drives fine.
If I can't find it, I'll go back to the mechanic, but he's very busy and my truck took way more time than we expected, so it won't be quick to get back in.
This is going to be a long one, but bottom line is, had some things repaired and now we get P0171 and P0174 (bank 1 and 2 LEAN). Trying to troubleshoot it.
Here is the immediate back story of repairs.
The truck sat for almost a year. When we decided to get it on the road again, it blew a brake line. So took it to the mechanic and purchased the stainless brake line kit to replace them all.
He dropped the fuel tank to access the rear brake line, and ended up also replacing the fuel pump (housing was cracked).
We had been having EVAP issues prior to letting it sit, so I had him replace the charcoal cannister, evap purge solenoid and evap vent solenoid (dorman parts)
He also replaced two calipers and the rear u-joint on drive shaft (probably irrelevant, but)
When it's really cold, the idle will stumble until it warms up. If you put it in gear right away when it's cold, the check engine light flashes and you get "P0300". But once it's warm, that goes away. If I clear the LEAN codes and drive, they both go PENDING, and Bank 2 usually sets the code, and bank 1 stays PENDING.
What I've tried:
1. I used MAF cleaner on the MAF
2. I sprayed throttle-body cleaner on vacuum hoses while it's running, listening for a surge.
3. I check fuel pressure (40-45psi) primed with key on, engine off.
If it wasn't for the engine light, once it starts warming up, I wouldn't know anything was wrong. It drives fine.
If I can't find it, I'll go back to the mechanic, but he's very busy and my truck took way more time than we expected, so it won't be quick to get back in.
