Contour Enthusiasts Group Archives Forums General Troubleshooting Check engine giving codes PO171 and PO174

O.K. I looked for a possible for fix for the following:
PO171 and PO174 which reads on from the program "system too lean - Bank 1" and "system too lean - Bank 2"

Unless I missed something here I did not find a cure or any "How To" posts. Does anyone have a clue? I just picked up a 98 CSVT and cannot license or DEQ the thing until this code is cleared.....

Any help would be sweet!

Usually a vacuum leak.

PCV hoses and intake manifold gaskets are really common sources. Could be a intake hose leak or a MAF sensor issue.

Click on SEARCH, select Troubleshooting forum, keywords "P0171 P0174", select AND, select ALL POSTS, and see the results of numerous previous discussions.

Steve

Welcome oregonSVT .

From TSB,

P0171 - System Too Lean (Bank 1) The Adaptive Fuel Strategy continuously monitors fuel delivery hardware. The code is set when the adaptive fuel tables reach a rich calibrated limit.

Fuel System:
�· Contaminated fuel injectors
�· Low fuel pressure or running out of fuel (fuel pump, filter, fuel supply line restrictions)
�· Vapor recovery system (VMV)

Induction System:
�· MAF contamination
�· Air leaks between the MAF and throttle body
�· Vacuum leaks
�· PCV system concern
�· Improperly seated engine oil dipstick

EGR System:
�· Leaking gasket
�· Stuck EGR valve
�· Leaking diaphragm or EVR

Base Engine:
�· Exhaust leaks before or near the HO2S
�· Secondary air concern

Powertrain Control System:
�· PCM concern

Welcome aboard. How many miles on your rig? Along with showing the check engine light, how is it running otherwise?

Thanks for all the input guys. Also thanks for the warm welcome. I look forward to being around here more. As soon as life allows me some more time.

Well, after working on those codes for about 6 months, mine ended up being a combination of crappy K&N filter, fouled maf (even after cleaning it 10+ times) and a bad oil pan gasket. I would try the MAF cleaning first with a real MAF cleaning product. In addition if you use a K&N, make sure it's not over oiled as I am sure that was what kept fouling my MAF. Let us know your results.