my sevice engine soon light come on in my 2002 Mercury Mountaineer. the code reads Po171 Bank 1 system too lean, 2 code Po174 Bank 2 system too lean, 3 Po300 Random- mutiole misfire derected,

Perry Wilkerson

Asked by Jun 01, 2013 at 01:04 PM about the 2002 Mercury Mountaineer 4 Dr STD AWD SUV

Question type: Maintenance & Repair

my car is not stalling but when im park it seems as if it wants to cut off, it does not do it when im driving. auto zone said it could be my air fiter sensor and its setting off the rest of the codes. what you think it could be.

6 Answers

I'd go for a tuneup~

1 out of 1 people think this is helpful.
Tom Demyan

P0171 & P0174 is a vacuum leak. Find that first then do the tuneup as Judge suggested.

2 out of 2 people think this is helpful.
Best Answer

might be a air leak between injector and heads,gasket,or fuel filter,or oxygen sensor. hate to say it but probably need to take to someone to do a diagnostic check, maybe ford place. hate all this complicated crap !

1 out of 1 people think this is helpful.

when you really have an EXPERT on a particular vehicle, NO time is wasted guessing, but the expert goes right to where the problem is and does not waste time guessing...quite, not me~


The vacuum leak is probably causing the p0300. I wouldnt worry with a tune up unless it is time for one.

3 out of 3 people think this is helpful.

And what is the parts store talking about "air filter sensor" they will hire anyone at those places I swear.

3 out of 3 people think this is helpful.

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