first off my truck is running like (word edited out By admin) it has a very rough idle at around 800 rpm. Gas mileage has dropped to about 3mi/gallon . the weird part is i had to take a bit of a long trip to a neighboring county(only like 25 mi wich is long for me) I got there it was still running fine. 4 hours later during lucnh break is when the crap hit the fan.......its running really loud now whole truck vibrates when at rest. Changed the oil today thinking the oil was bad b/c of off-roading while it was wet out. Didnt do a damn thing(it was due for an oil change anyway) Im thinking about taking it to the shop b/c the service charge would probably be less than all that gas i've lost. Any suggestions of what could be causeing this problem?
Thanks a mil.
Tim

 

The first step would be to get a $30 code scanner from Autozone, read the codes, and compare them to a chart in Haynes or on-line. You bring it somewhere, that is the first thing they will do, read the codes.

 

 

yes, it would be pretty silly to take it to the shop just to find out it was something very simple.

 

On a 1992 you can use the CEL, check out pulling eec-iv codes in the tech info post.