Jim Grant's Tech Tips

'93 Jeep Grand Cherokee, Coil Problems

Q: I hope you pick my problem . I have a ‘93, Jeep Grand Cherokee with the 5.2L engine. Recently I have had to replace THREE coils to keep it running ... It ran for the first 100k miles great and then started hesitating or running rough - no one could find the problem until the coil finally failed. After replacement it ran great for 2-3 mos, then quit on the road while driving with no warning! After replacing the coil again with a Chrysler part - it ran for approx. 3k before starting to run rough and momentarily hesitating. I replaced the coil again (third time) and it ran fine for about 100 miles but its starting again! I have replaced the spark plugs, spark plug wires, distributor cap etc. Why is it "eating" coils - a friend had to have 3 replaced before his problem went away - his has a 94 ... Are they bad coils? Or is something else wrong? Distributor? Computer?....... Kelly

A: Did you update the coil? ALLDATA Information System shows Technical Service Bulletin # 08-35-93 addressing a no start, hard start or poor engine performance problem caused by an internal shorting of the ignition coil. The fix is and updated ignition coil and wiring harness package. The first ignition coils just didn’t work right, the fix corrects this condition. Installing the updated kit should relieve you of future ignition coil problems.