1992 jeep cherokee - check engine light comes on intermittently - what's up?

Question

All basics covered; oil, antifreeze, etc. Can sometimes go a week without light coming on. Does run a bit rough at times but it does have 127,000 miles on it. Please give me options before I take it in for a look as I do not have a reliable mechanic as of yet. Thanks!

Answer 1

You can take your car to AutoZone and they will scan your car for free and tell what the light is trying to tell you.

Good Luck

Answer 2

if you dont have a way to get a scan tool into the truck, then I suggest buying a Chilton manual for it. Being an older car you should be able to "jump" the ports. The manual tells you exactly how to do it. It's not tricky but its not something that can be told in a writing like this. You need to see what I'm talkin about. You could also try replacing the o2 sensor/s. As they heat up and cool down you can throw a code. They have a hand in the rich/lean fuel mixture so that can cause rough running. Plus it is intermittent. Bad plugs and wires can also cause this problem. As can arcing in the distributer cap. do a proper tuneup and your problem will be cleared.

Answer 3

If you have a manuel, it will tell how to get codes that will direct you in the right direction.Check the spark plug wires; at night to see a spark from the wires to any metal surface. Check the spark plugs, Check the fuel filter to see if it need replacement, Drain the gas tank from a plug at the bottom of the tank; just a small amount for water in the tank, Check any small vucuum hoses that go to the intake manifold for cracks or loss fittings, Check the E.G.R valve function, and make sure that intake port is not plugged.

Answer 4

I would run some Heat through the fuel tank. Is it vinyl? If so, it's collected moisture and I'd bet the codes are coming from the O2 sensor, but it can throw codes without being bad if there is water in the fuel.

Answer 5

check your onboard comp.,and see what code comes up.it should tell you what is happening.