i have a 98 grand cherokee with the 318 engine and 136,000 miles .been a very reliable vehicle. Question- the check engine light just came on the other day, but the engine is running fine, all fluid levels were good, engine not overheating. No other problems , save for the check engne light being on.
Any hints?-----converter?? It is rattling a little so i know its old but i don't smell raw eggs.
Any help?
Thanks guys---p.s. Its the ol-ladys car so she does not run it very hard At
All!

 

Could be as simple as an O2 sensor going. Take it to almost any chain auto parts store, they'll pull the code for free.

 

Thanks Hammer for the info. This has been a great vehicle, very reliable from day one of ownership. The 318 is very fast and has plenty of power even after 135,000 miles or so.
once again thanks.