Topic: I go over a ruff patch of road my jeep dies

[Yellowcritter]

Posting for a friend off of our local club's web site.


Heres the problem when I go over a ruff patch of road my jeep dies and then contiues on .The check engine light comes on and goes back off really fast Ive checked connections and all seem tight. Idles good and runs ok on paved roads . Oh before i forget its not a total die, the radio still plays while its dying not a total shut down any ideas?

[Jeffy]

What year?  Did he check for CEL codes?  I'd suspect the power distribution box, ground cable at the block, coil, distributor....

[Yellowcritter]

97 TJ ... going to pull codes tomorrow. I kind of thought along the same lines as you, but he said he had checked the ignition system and grounds. I told him to just drive around the mall on smooth pavement. But they have speed bumps too.

What year?  Did he check for CEL codes?  I'd suspect the power distribution box, ground cable at the block, coil, distributor....

[jfrabat]

I assume you already checked the battery connectors, right?

[Yellowcritter]

I assume you already checked the battery connectors, right?

We took them off and cleaned them at the battery and checked all other connections. We also checked and it is not throwing any codes, guess light is just coming on due to the engine dying. He is replacing the coil, wires, rotor and cap today. Haven't heard if that helped or not yet.

[Jeffy]

If the CEL came on then it will have a code.  Even if it didn't come on doesn't eman it doesn't have a code either.

I'd also check the connections for the IAS and TBS and maybe the vacuum lines.

[Yellowcritter]

Thanks, we checked those connections and we're going to run an ohm meter on everything when time becomes available to check for shorts. We used two different readers and neither found a code which was strange to me. Never heard of one and not sure if it's possible, but could there be a short inside the ECM?

If the CEL came on then it will have a code.  Even if it didn't come on doesn't eman it doesn't have a code either.

I'd also check the connections for the IAS and TBS and maybe the vacuum lines.

[Jeffy]

Thanks, we checked those connections and we're going to run an ohm meter on everything when time becomes available to check for shorts. We used two different readers and neither found a code which was strange to me. Never heard of one and not sure if it's possible, but could there be a short inside the ECM?

Did you try the ignition trick for the codes to appear on the dash?  Although I don't think you'd ever have them appear on the dash and not on a reader.  Could have been cleared though too...

[jfrabat]

Thanks, we checked those connections and we're going to run an ohm meter on everything when time becomes available to check for shorts. We used two different readers and neither found a code which was strange to me. Never heard of one and not sure if it's possible, but could there be a short inside the ECM?

A friend of mine shorted out his ECM (his is a 4.0L), but the Jeep just died; it did not act like what you are describing.  So I doubt that is the problem...

Felipe

[Yellowcritter]

Finally found the problem, one of the wires going to the coil was broken inside the insulation. Replaced the wire and took it for a test drive and all was well. He is going to take it to the trails this weekend to see for sure, but we think we have fixed. Thanks for the replies. Mike

[jfrabat]

Glad to hear all is well now!