My car keeps throwing a P0171 code which means my car is running lean on the driver's side I believe. What could cause this? Could a slight exhaust leak before my O2 be enough to set this code or is there more to it than that? Anyone else have their car throw this code and fixed it? Usually if I pull the PCM batt fuse to reset the computer it won't throw the code for a day or 2 but then it will come on when driving. The car seems to run beautifuly otherwise so I don't know what the deal is.

Myles

 

I just had my 97 Formula scanned yesterday and came up with the same code P0171. Did you get answers to the cause of the lean condition? My service books are not very helpful trying to isolate this condition.

 

An exhaust leak will cause that if its big enough.

If the passenger side fuel trims are kosher, that's what I'd be suspicious of.