ok guys so i have a 04.5 i cut the cat and muffler out of and straight piped sat afternoon, drove around sat night and all day sunday, went out to start it and now the check engine lights on??? could the exhaust have done this?? i work at a heavy diesel shop on macks and volvos and have access to a scan tool on monday to see what the code is but untill than this is just pissin me off

 

Naah I dont think thats it. Do the three key trick get the code and then post what code it is so we can help.

 

3 key trick?

 

turn the key to the acc position then turn it to on, but not to start. Cycle back and forth between acc and on 3 times and any codes will show on the dash where your mile# indicator is. Do a search there may be more detailed instructions. Its easy just make sure not to turn the key far enough to make the truck turn over.

 

code p1757

 

Governor pressure, do a search on that code from the looks of posts it can be common.

 

can i clear it by pullin the batts?

 

You can go buy a cheap code reader, that will clear codes. You can drive it, it should go off on it's own. Or you can try the batteries.