P0171 and P0174
#41
A bad PCV Valve also caused PCM 174 (System Too Lean ) along with the poor fuel economy . I am not an expert and since you're talking about about this code I thought I should pop in .
My dad's car throws this code and it was in the service yesterday and they called they will replace PCV , it was a smoking gun in our case .
My dad's car throws this code and it was in the service yesterday and they called they will replace PCV , it was a smoking gun in our case .
#42
I just need to replace the O-rings on the breather hose to solve my P0171/P0174 vacuum leak problem. Does anyone know the OD/ID size in mm for the two O-rings. I really don't need to replace the entire breather hose. I've cleaned the TB an MAS sensor. The O2 sensors are good. A/F ratios are super lean.
#44
#45
A bad PCV Valve also caused PCM 174 (System Too Lean ) along with the poor fuel economy . I am not an expert and since you're talking about about this code I thought I should pop in .
My dad's car throws this code and it was in the service yesterday and they called they will replace PCV , it was a smoking gun in our case .
My dad's car throws this code and it was in the service yesterday and they called they will replace PCV , it was a smoking gun in our case .
#48
Hi , the same problem I have on my str.Please advise !
I have checked shake test for any leak , replaced maf , replace breather valve, checked throttle body done almost everything, eml light did not came until a petrol fill up, after that again !!!!!! What to do guys this jag is a painnnnnnnnnnn
I have checked shake test for any leak , replaced maf , replace breather valve, checked throttle body done almost everything, eml light did not came until a petrol fill up, after that again !!!!!! What to do guys this jag is a painnnnnnnnnnn
#50
#52
#54
Success!!!!
My 2003 3.0 v6 has now travelled several hundred k's without fault...
I was forced to replace the battery when the old (original) one failed and used that as the catalyst for a real good check... There were no vacuum leaks... Air filter was filthy so was replaced.
OBDII monitor showed MAF flatlining... A clean with special spray only delayed the fault.... A new MAF has fixed the problem...
Cheers,
I was forced to replace the battery when the old (original) one failed and used that as the catalyst for a real good check... There were no vacuum leaks... Air filter was filthy so was replaced.
OBDII monitor showed MAF flatlining... A clean with special spray only delayed the fault.... A new MAF has fixed the problem...
Cheers,
#55
Back to the drawing board. MAF sensor cleaned, new clamps on TB boots and air breather hose has new O-rings. Took a 60 mile drive and the P0171/174 codes are back with the ECL. Can't find a vacuum leak anywhere else. This series of codes started showing up after a 80k check on the car. Any thoughts?
Also, have these scans:
Also, have these scans:
Last edited by nail24fac; 12-03-2013 at 09:01 AM.
#59
I had these recurring on the 05, no joy finding vac leak. Live data didn't really reveal anything until I started to compare it to the 03 at similar rpm/load. Then noticed the MAF on the 05 was consistently reporting higher airflow than the 03 for similar rpm/load. Swapped MAF's between the cars and the codes went away for about a year, but eventually surfaced on the 03 which was now running the 05 MAF. Swapped 'em back to cure the 03 and ordered a new MAF for the 05. No codes in the 3 wks I shifted the original 05 MAF back to the 05 car until new one arrived and I found time to fit it. Everything fine for awhile, now the 05 periodically sports a "MAF invalid or out-of-range code" don't remember the number. May put the original MAF back on now that it's had a year or two's rest......
Of course...that was all backwards because if the MAF was truly over-reporting, the O2 sensors should have been seeing "Rich" vice lean, but I didn't try to reason it beyond "Swap the MAF's and both cars are happy happy"
Of course...that was all backwards because if the MAF was truly over-reporting, the O2 sensors should have been seeing "Rich" vice lean, but I didn't try to reason it beyond "Swap the MAF's and both cars are happy happy"
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nail24fac (12-04-2013)