check engine light on with code that says fuel trim malfunction??

[GstRacer]

what dose fuel trim malfunction mean how do i fix it?

 

[1fast97gsx]

what mods do you have? If you have an safc its just not set right ...

 

[99 turbo GS]

i have a '97 gs-t with a 1g BOV. i keep pulling that code. ALL STOCK except the BOV.

 

[toojung2die]

It means your A/F ratio is so far out of whack that the ECU cannot compensate. A/F ratio is measured by the front O2 sensor. You probably have a leak in your intake after the MAS or your O2 sensor is going bad.

 

[Killa_dsm]

I have had the same problem. Solved it by changing out the front o2 sensor in the o2 housing.

 

[matthewdesigns]

This can also be caused by a fuel shortage, exhaust leak, and a few other things I can't remember off the top of my head. I got a list of what can cause this from the dealer's diagnostic book. I had the same problem and solved it by rewiring my fuel pump for more flow. I have not thrown the code since.

Most of the threads I've seen regarding this problem have been solved by replacing the o2 sensor, like toojung and killa suggested, though.

GstRacer: Is it possible your fuel is off a bit? I'd guess you have a pretty good handle on that with DSMLink, but maybe adding a little will solve the problem if it doesn 't make you run too rich and throw off your tune. Is the o2 sensor reading properly at idle and WOT? This would of course point to it being bad, and not another cause.

99 turbo gs: Try making a friend at the dealer and getting the list of potential causes. Or just jump in and rewire the pump...not a bad idea anyway.