Contour Enthusiasts Group Archives Forums General Troubleshooting multiple codes with no problem help!!

I just had some codes pulled and im getting A P0401, P0420, P0171, P0174. I know what they all mean but I'm a bit confused. I had the intakes completely cleaned by ford a year ago, new plugs, wires, upstrem O2 sensors in both banks, and coil pack. The car runs perfectly under 124,000 miles,I mean no hesitation, no loss of power, not even a loss in gas mileage, maybe a little but not much and it all depends on my driving habits. Its a 2.5 svt all original. I need help what can cause these codes and how can I fix them. hanks for anyones help.

Likely three separate faults:

1: P0401 - EGR ports clogged or DPFE faulty. Plenty of history on this in prior posts.

2: P0420 - Cat converter below established efficiency. Also plenty of history in prior posts.

3: P0171 & P0174 - Probable air leak in intake system. Might be intake gaskets, PVC hose, or any other part of the intake tract after the MAF sensor. Once again, plenty of history in prior posts.

Use the code(s) as your keyword for a search.

Steve

P0171 & P0174

Just a follow up - several members ( and I have them as well) have noticed the PCV hose getting nearly microscopic cracks allowing un - metered air to enter. I would suggest using the starter spray method to determine where the air is entering. Most likely a gasket or MAF leak.

hey everyone! Thanks for your help. I got to work on these codes yesterday, i took out the upper intake manifold and man was it full of crud and grudge and other stuff i wont mention here, even the lower intakes and the tb. Well i cleaned it all as best i could changed all the gaskets and much to my suprise i got an increase in power and it idles alot smoother. So much for ford cleaning my intakes, what a rip off!! Anyway the codes are gone and i cant wait to find out how my gas mileage will do. thanks again.