check engine light is on and has custom exhaust, can that be it?
Ford Q&AAsk Your Question
1998 Ford Mustang Question: o2 sensor
Answer #1sinautoscan.com October 25, 2009, 15:35Master
It could be the CAT if it was removed i would get a diagnostic to see what the problem is autozne does this for free.
Answer #2Visitor, April 06, 2010, 09:07
I had the same promble (check engine light). I stop using cheap gas and after 3 tanks of gas (plus), the light went out.