98 Oldsmobile Regency - P0171 code issue

Good morning to all fellow auto profesionals, I am a service manager at sa local shop here in Port Richey Florida. I curranty have a 98 olds regency in my shop with a code P0171 code in it and we a having issues diagnosing the problem:banghead:. What was done to car follows.

plugs
wires
lower intake gasket
upper plenum gasket
O2 sensors
fuel filter
fuel induction service
coolant temp sensor

also during diagnostics reading misfire data shows no misfire data during closed loop however it did create multiple misfires while in open loop mode. I would love some help on this issue and hopefully I could make my customer happy:confused: . Thank you for your interest and help in this matter.

Sal

Well, the pcm sees this engine as running lean as you know, I would be looking for air entering the engine unmetered, the o rings under and on the map and pcv first place to look, then just the normal vacuum leak issues. A misfire can cause this code but it usually won't set the misfire code if it precedes it.

i had the tech look that over again, as he started to check the o-ring on the map sensor and the whole thing just come apart into two pieces. we are expecting it in a few hours, we will let you know. thanks again:biggrin: