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Does anyone elses run after the key is off

B

btm757

NAXJA Forum User
Location
Norfolk / Chesapeake, VA
I have a 94 i just picked up with a 4.0 and after you turn the key off it still runs for aprox. 5 secs i was wondering if this was a normal condition or if something would cause it to run after the key is off?
 
That sympton is call "dieseling"...usually caused by carbon buildup in the engine...you can try cleaning it out with Seafoam or Mopar Engine Cleaner from the dealership...old timers use to pour or spray a little deionized/distilled water into the throttle body to acheive the same cleaning results, but I recommend the Mopar engine cleaner...more expensive, but more effective.
 
Not so sure about the carbon thing but if you are looking for a good cleaner for the carbon and fuel system, you can't beat BG44k.

I tend to think there is a problem with the power latch relay.
 
I got access to all the mopar goodies at work. I will do a throttle body service on it when i get a free moment at work.


old_man where is the power latch at? and how do i check it?
 
You have three or four relays on the passenger fenderwell, nearest the firewall is the oxygen heater relay, next is the fuel pump relay, third is the B latch relay, and fourth is the a/c relay if so equipped.

Dieseling is an oddball run-on caused by heated carbon deposits, if the engine wants to run on and seems normal and smooth it isn't dieseling.
 
Play musical chairs with the relays. They are all the same type.

If not a relay, you most likely have a bad ignition switch.

Good luck.
 
Or another thing could be some PO could have wired the fan into the ignition so when the ignition switch is turned off the fan is still turning IE putting eletricity back into the ignition and keeping the engine running untill the fan quits spinning
 
XJeeper87 said:
Or another thing could be some PO could have wired the fan into the ignition so when the ignition switch is turned off the fan is still turning IE putting eletricity back into the ignition and keeping the engine running untill the fan quits spinning
Click to expand...
this happened to me. i had it like that for a short bit before it went through a relay. after the relay was in no more problems
 
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