Hello Jeep world. I'm new here and to the Jeep community. I'm trying to help my son find the answer to his problem. I did some searching here and didn't see anything that sounded like the issue. First it is a 98 Grand Cherokee . When you start it runs great for a few miles down the road and all of the sudden it will miss and pop and dome lights will flash. He says when this happens it will make like a beep sound 1 time. Dash shows no check engine light.

 

First off welcome to the community.
Second just a little more information needed. Does it actually shut off when it does this or does it continue just running rough?

 

Thanks for the reply. It continues to run but loses power due to the missing and forgot to mention if you pull off to the side and shut it off and start it right back up it will run fine a few more miles and start doing it again.

 

Well I would say that this is beyond me.

 

Okay, well thanks for thinking about it anyway.

 

Well my first thought is that the radiator cooling fan is kicking in and pulling either way to much current or the alternator is not able to feed it enough current and is robbing the ignition of sufficient electrical current to function correctly, but I have no idea how that would make the dome light flash.

 

If I am correct all ZJs came with a mechanical fan not electric.

 

I know many issues that can cause those symptoms, sounds like a fuel issue. Do you smell fuel, partially combusted fuel, no fuel or lean scent, that's what a mechanic can sense. It is extremely important to know if the engine is well maintained, wires, plugs, filters, battery wiring, etc, or helping here is moot. Have a mechanic friend drive it, as long as the vehicle has been maintained he should easily be able to isolate a problem like this. Other component failures like the crankshaft or camsfhaft position sensor can imitate these symptoms.

 

Yeah, the one that I have utilizes a mechanical cluch fan not an electric fan.

 

sorry, I thought the electric fans went further back. but like I said I don't know of any way the electric fan, if it had one, or the fuel system for that matter, can cause the dome light to flash. still sounds like an electrical problem, or a computer problem to me. And if it is making a warning chime it should be logging a code.

 

Sorry. I did not to concentrate that, I picked up on the misfire and popping, running and stopping, then cooling down and restarting. I've seen freak electrical create issues like this and it all boiled down to a bad PCM. I've also seen among other problems mechanical failures that caused fluctuations in current that made lights flicker or gauges go haywire, a short can even send voltage to lights causing them to illuminate with the switch in the off position. I don't know, I'm just some old dude on the net trying to help.

 

Well, He came to me yesterday and said he thinks he found the problem area so I went and observed what was going on myself. The running rough seems to have something to do with what the parts guy said is a air pollution gadget that starts clicking when this happens. My son unplugged it and he says it doesn't do it now. As far as the lights flickering , what I saw was both passenger doors keep saying ajar and keep turning the lights on and buzzer like when you open the doors. Totally different issue. Thanks guys for thinking about this, we'll see what happens.

 

Point of information. My 97 ZJ had the tow package and only a clutch fan.