hey guys i dont post alot but for this one i need some help.i went to advance auto parts 2nite because my check engine light keeps coming on and after i reset my ecu and they put it on the code scanner and it came up with two codes.....the 1st is an p0170 Fuel Trim Malfunction (Bank1).and the 2nd is....p0505 Idle control System Malfunction...those are the code that it throw but that all...i need some help on this one...Thankz guys....O forgot to say it was a 95 gst

 

I had the same problem but since I change my fuel trims and idle I just didn't worry about it. Car broke before I had a chance to research.

 

i found out that it may be my front o2 sensor and for the idle code my isc on the body of my tb...how much is the front o2 sensor and the idle speed controller

 

P0505 is the ISC, i had the same code a while back
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