dieseling
Thread Starter
4th Gear
Joined: May 2002
Posts: 4
Likes: 0
dieseling
Hey gang,
My 87(3.2) coupe ocasionally display the "diseling" effect (I think) after a nice drive.
Meaning that when I turn the off the ignition,the motor does not stop immediately. It would "run-on" for a quick 1-2 seconds before completely cutting-off. Any ideas what is going on? Also, besides being annoying, does this harm anything?
The spark plugs,rotor,and rotor cap has recently been changed! so I don't think it's one of those items causing it.
thanks,
tony
My 87(3.2) coupe ocasionally display the "diseling" effect (I think) after a nice drive.
Meaning that when I turn the off the ignition,the motor does not stop immediately. It would "run-on" for a quick 1-2 seconds before completely cutting-off. Any ideas what is going on? Also, besides being annoying, does this harm anything?
The spark plugs,rotor,and rotor cap has recently been changed! so I don't think it's one of those items causing it.
thanks,
tony
RL Technical Advisor
Joined: May 2001
Posts: 11,870
Likes: 75
From: Portland Oregon
Hi Tony:
Normally, dieseling is accompanied by that run-on and engine knock. If you are hearing these kinds of sounds after you shut the key off, its indicative of a hot spot in the combustion chamber thats providing a source of self-ignition.
This hot spot can be a small piece of incandescent carbon or a spark plug that is the wrong heat range (too hot). Doing an aggessive round of treatment with Techron or changing plugs to a cooler range, usually helps that a lot.
This situation should not be confused with the engien running on smoothly for a second or two after you turn the key off. That is usually caused by a lazy DME relay or faulty ignition switch.
Hope this helps,
Normally, dieseling is accompanied by that run-on and engine knock. If you are hearing these kinds of sounds after you shut the key off, its indicative of a hot spot in the combustion chamber thats providing a source of self-ignition.
This hot spot can be a small piece of incandescent carbon or a spark plug that is the wrong heat range (too hot). Doing an aggessive round of treatment with Techron or changing plugs to a cooler range, usually helps that a lot.
This situation should not be confused with the engien running on smoothly for a second or two after you turn the key off. That is usually caused by a lazy DME relay or faulty ignition switch.
Hope this helps,
Thread Starter
4th Gear
Joined: May 2002
Posts: 4
Likes: 0
Thanks Steve,
Like I mentioned, the spark plugs are new so there is a slim chance that my mechanic installed the wrong heat range plugs. Assuming that they are the correct spark plugs,and this annoying dieseling problem only happens once in a while. Should I ignore it if it does not damage other components later.
tony
Like I mentioned, the spark plugs are new so there is a slim chance that my mechanic installed the wrong heat range plugs. Assuming that they are the correct spark plugs,and this annoying dieseling problem only happens once in a while. Should I ignore it if it does not damage other components later.
tony
