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I had a Cel come up last night.. ran the obd2 reader can cam up with p0171 p0174. Thats the only codes. Was idling really rough at idle. Did some poking around and am pretty confident there is no vacuum leak. I work third shift so I cant really work on it till Monday. I noticed on the freeze frame data that my st fuel trim was 18.8 amd LT was 23 to 29 at idle...I cleared the codes.. .started it again amd it came nack....cleared again this morning then I left...drove home and when I stopped in the drive way st fuel -3 lt was 6 to 9 at idle. Tomorrow ill start with cl3wnimg the maf. It was reading .46 at idle and around 2.6 lb/m driving home..
Last edited by Leewebb7; Mar 29, 2026 at 04:01 PM.
2004 3.0, over 360,000. I did a ghetto smoke test...couldn't find a leak. I even sprayed carb cleaner all over the motor while running...no change. So today I disconnected the neg battery cable, removed maf sensor...cleaned it....removed iac....cleaned it....removed intake hose and cleaned the throttle body out....put everything back together and now it's running little rich...probably from all the carb cleaner and hooking the battery cable back up....hopefully it just needs to relearn. Im pretty sure there isnt a vacuum leak.
You might’ve corrected it. Since it’s not on one bank, you can rule out an injector or something on one side. It has a lot of miles and have you ever changed the O2 sensors? That wouldn’t be the case right now because it would be odd that they both be not working at the same time. Still they’re only good for 100,000 miles or 10 years. I guess just keep your eye on it for a while.