This only happens when the engine is warm, but when you turn the ignition off, it dies, then starts up for a second or two. It occasionally acts as if the starter bendix make be going out as well during crank, but has always cranked. May or may not be related. Any ideas?

Thanks

 

To date: I replaced the crank position sensor and this seems to have helped the bendix problem. Still having problems with this dang run on for a second after the ingnition is turned off. I am thinking possibly a timing problem...any suggestions?

It is an erratic problem, but I have searched this forum top to bottom and can't find a similar problem.

 

Crank Position Sensor provides your timing and fire pulse for your electronic fuel injection system. Cam Position Sensor inside the distrbutor, under the rotor plate, does ignition timing, Bro. Hope this helps.

 

my money is on your key switch...it shuts power off to everything when turned off. you can verify this by taking the steering colum cover off finding which wires get 12V ,when the key is turned to ACC then see if they stay Hott when turned off. or you can just replace the switch.

 

Unless he has a Renix Jeep, then the switch is on top of the column inside the dash, but not hard to get to. We need to know what year your ride is.

 

Tried the switch deal. Didn't help at all. I am still leaning towards a timing problem and will get this checked out. Checked for vacuum leaks...haven't found any. Also, I hate to, but I am going to try a mid-grade gas next time.

 

run on is usually a heat buildup problem from wrong plugs or carbon buildup
it could be timing or ignition
make sureyou have the right plugs and they are clean
this my be a good time to try sea foam

 

I put in the bosch 4 prong plugs a few months back. I heard somewhere that a basic Champion plug is the best for less heat. I may try putting in a set of these. I also read in a Haye's manual about possible carbon buildup. What's the remedy for that...head removal?

 

Did you wire the electric fan to run any time the key is on???

The electric fan spinning will generate enough current to keep the ASD relay energized after shutdown for a couple of seconds.

 

sea foam

 

Get rid of the JUNK Bosch sparkplugs and get the correct OEM heat range Campion plug for your Jeep's motor. I gurantee that will fix your problem. Bosch plugs are straight up "and I might add, overpriced" GARBAGE!!

 

I have changed so many plugs lately that I forgot what I had put in. They were the champions (bosch went in a nissan of mine)...so this shouldn't be the problem. What's the sea foam deal??? I've recently removed the throttle body and gave it a once over with carb cleaner.

The only thing that I have done to the electric fan is replace the relay. When I first bought the jeep and brought it home, the fan continued to run even after the key was removed. The relay solved this and I don't think this is the issue...but who knows.

Thanks for everyone's input on trying to help me figure this one out.

 

Update: The ASD relay was the problem. The fan relay is seperate!! Evidently, the contactors continued to contact or arc enough to keep the circuit closed for a couple of seconds.

Thanks for everyones help and I hope that my solution helps someone in the future.

 

I wired our fan to run any time the key is on. That is what keeps ours running when the key is turned off.
Thanks for the idea. I will put a relay back in.