P0171

You've described the intake gaskets to a T... I'll bet it runs rough when cold and smooths out when warm....

Yep. It does. How hard are those to change out? I'm pretty handy with tools.

thanks, Murray

Real easy... I did mine in about 4 hours with the help of a haynes' Make sure you have a long star drive bit to reach down to the top manifold bolts remove the top cover and you can see the front ones theres 8 in there somewhere.The bottom manifold has conventional bolts.

Dick

I think you're talking about the SOHC

He has OHV

New gaskets didn't fix it. Ran for about 1 day then P0171 showed back up. Anybody have any suggestions where to look next? O2 sensor? Bad injector(s)? I already checked all the vacuum lines while I had it apart and they were fine.

Thanks, Murray

Would be nice if you quoted some of the history of this thread - couldn't find anything... Have you checked fuel pressure?

I have heard of a FEW people that ran some good fuel injector cleaner thru the tank and got this code to clear. Try NAPA and see if you can find bg44k - about 25.00 a can but it works well. Techron is also effective, but the bg44k works better. Might as well do your fuel filter if you have not chenged it recently.

Other UNusual stuff that causes p0171

1. Dipstick tube sucking air - bad seal
2. PCV hoses sucking air.
3. Cracked air intake tube between MAF and throttle body - pull it and check it carefully for cracks.
4. EGR valve loose, or leaking.
5. Tube from exhaust manifold to EGR valve cracked, or loose
6. Hose from fuel vapor recirc system (evap solenoid) to intake manifold cracked or leaking.
7. Loose throttle body bolts
8. Exhaust system leak before O2 sensors (since you are setting p0174 that would require TWO leaks)

If you check all this stuff, do the cleaner and fuel filter, I think you have good chance of finding your issue.

If you feel like it, post your LT and ST fuel trims at idle, 1500 rpm, and