trouble codes

Can and how do you check trouble codes on a 89 Jeep Cherokee? I dont seem to have a check engine light when I turn on the key. I have a 4.0 liter engine. Anybody know?

the computer in the 89 doesn't store trouble codes. the best you can do is get a reader (like the snap-on) that will give you real-time readings from your sensors, but it's not a lot of help if it wont start.

Thanks for the info

to only way to get any codes is take it from the dealer

even the dealer can't retrieve the codes on an '89 because the computer simply does not store any. when you shut the key off it completely forgets any problems it had and starts fresh with the next turn of the key.

the best you can do is get a reader that gives you real-time data, it will tell you what the readings are from each sensor and you have to check to see what the normal range is for each and hope to find the problem that way.

even the dealer can't retrieve the codes on an '89 because the computer simply does not store any. when you shut the key off it completely forgets any problems it had and starts fresh with the next turn of the key.

the best you can do is get a reader that gives you real-time data, it will tell you what the readings are from each sensor and you have to check to see what the normal range is for each and hope to find the problem that way.



a friend of mine has an 89...cherokee pioneer,4.0 liter 5 speed,it sometimes runs high idle and other times sputters and wants to stall...if he shuts it off and tries to restart it-it still messes up.....if he shut the key off,then cycles the key on and off 3 times then starts it,it runs super for a while then messes up again....my point,they do hold the codes there is just no obd connector.....it must be hooked to the ecc directly to read it,and this takes a dealers' equipment.