Topic: Jeep Doesn't shut off when I turn the key to off

[BigCountry]

I'll preface this with the standard info, 1991 YJ, 2.5l, ax-5, electric fan.

My jeep no longer shuts off right when i turn the ignition to off. it continues to run for 15-20 seconds and then dies. i've taken it to an auto electric shop trying to get it fixed, and they could not find the source of the issue. He checked to see if the alternator wasn't stopping, and alternator is fine. he also plugged in a scanner to try and get some codes, and the scanner wouldn't recognize the engine at all. like it didn't have any input whatsoever. i also just found out that the engine is a reman and there are no other identifying marks.

Has anyone had a similar experience with this type of issue of the jeep not shutting off?

[BigCountry]

also the guy that put in the electric fan wired it so it is always on whenever the ignition is on. that was done at a jeep shop, along with replacing the temperature sensor that goes to the computer from the thermostat housing. not sure if those have anything to do with it, as the auto electric guy checked those.

[Bounty Hunter]

You may need to adjust or replace the ignition switch at the base of the steering column, on the top side of the column.

[BigCountry]

You may need to adjust or replace the ignition switch at the base of the steering column, on the top side of the column.

i was told they tried that, but i'm not exactly confident that they actually did that.

[sharpxmen]

is not autoignition is it? does it idle just fine or erratic once you turn the key off?

[Jeffy]

If it's running normally then just quits then it might be the ignition.  If it's 'dieseling' then it could be carbon build up in the cylinders.  Or since it's a reman. high-compression.

[Torch_Ind]

If it's running normally then just quits then it might be the ignition.  If it's 'dieseling' then it could be carbon build up in the cylinders.  Or since it's a reman. high-compression.

91 is that carb?? 

[BigCountry]

nope. 91 is TBI. and the engine idles just like normal for like 15 seconds and then finally the rpms drop and it cuts off. when i shut it off, all my gauges cut off at the appropriate time of me turning the key. my voltmeter, tach and everything except the clock go to sleep.

[BigCountry]

also noticed the exhaust smells a little rich. i was told timing and mixture were fine tho. as far as the high compression, wouldn't that have been an issue that started years ago? i've had the jeep 4 years now and i've always run 87 octane, without this issue. engine was swapped in before i got it.

on another note, i just got the jeep back from getting my crank pulley replaced and everything aligned. old one had a one inch long chunk missing from the back retention ridge, kept shredding belts. shop had to mill out .3" on the rear mounting surface of the crank pulley to put everything in alignment. now i have a serpentine SCREAM i have to deal with. tightened the belt up, but didn't help at all. ran it for 3 hours saturday driving around trying to get it to break in and stop, but no help. taking it back in tomorrow to get them to fix it. this time i'm not paying for it tho.

[chardrc]

nope. 91 is TBI.

a 91 TBI .. last year of TBI was 1990 last time I checked.

[sharpxmen]

i'd guess it's a relay that's not disengaging (if it's not the ignition contact) from what you describe but it's a bit strange since you're saying that your gauges are active while doing this.

i also thought '91 was MPFI btw.

[Bounty Hunter]

nope. 91 is TBI.

'91 is the first year for MPFI, the 4cyl TBI is '87-'90.

[Jeffy]

Yes 1991 is the first year for MPFI.

[Torch_Ind]

Yes 1991 is the first year for MPFI.

could it not be a early 91 "production date 90 but listed 91" ?

[Jeffy]

could it not be a early 91 "production date 90 but listed 91" ?

No, 1991 production would have started selling in late 1990.  You might get a 1990 that wasn't registered till 1991 but it will still be a 1990.

The only exception would be an Export Jeep.