Still runs after ignition turned off

gerrywalshe

On occasion my Elkie's engine continues to turn over after I turn off the ignition. It will chug to a stop after a few seconds with a horrible burning smell coming from the engine.

This does not happen all the time. If I start the car and drive for a while, it stops normally. However, if I start from cold and let it idle for a while, then turn the ignition off, it will chug, chug, and eventually splutter to a stop.

Any ideas?

464elky · Posted: Thu Aug 21, 2008 7:24 am Post subject:

It sounds like the choke maybe taking too long to come off and keeping the idle too high after the engine is warmed up.
I would guess an older higher mileage engine that has some carbon build up issues.
You can start running a higher grade fuel in it or try some of the carbon cleaning products.

Anybody else?
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e_16 · Posted: Thu Aug 21, 2008 11:10 am Post subject:

my 84 used to do this on occasion. I think its called dieseling? After accelerating or idling for only a minute or so and then turning the key off, the engine would run for a few more seconds and sound horrible... I lowered the idle screw a bit and it fixed the problem
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CANTED · Posted: Thu Aug 21, 2008 6:48 pm Post subject: run on

Make sure your base idle is not too high. A carbon cleaner like Neil mentioned is a good idea. If you have an automatic trans., turning the ignition off while in gear may help.
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old_coot · Posted: Fri Aug 22, 2008 9:45 am Post subject:

SEAFOAM---been there done that...go to the parts store and pick up a bottle for about 7 or 8 bucks and follow the directions---I'm not usually big on using foreign products in an engine but this is one that works as advertised---I would not however recommend using it in the oil, there are some engines that just can't survive being cleaned that thoroughly...........Dan
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Elky77 · Posted: Sat Aug 23, 2008 12:32 am Post subject:

It IS called Dieseling. Your carb is putting out too much gas that isn't getting burnt.

Adjust the fuel mixture, jet settings, idle speed, chock settings, etc.

When you turn the key off, it should shut down like a brick hitting the pavement.

Of course, this means when you're running, you're putting out too much gas and not enough spark. Wasting gas, causing build-up, and not getting the maximum power possible.

Use a good garage mechanic if you aren't capable yourself.

let us know how it turns out,

Elky77

hemi57 · Posted: Wed Aug 27, 2008 10:33 pm Post subject:

Here in Australia we call it "pre-ignition".

Same solution to fix the problem as in the US though Poke Tounge

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dougs85 · Posted: Wed Aug 27, 2008 11:06 pm Post subject:

Idle RPM is the very first thing to check. It's the cure most of the time. And it does not cost anything.

Doug
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old_coot · Posted: Thu Aug 28, 2008 9:39 am Post subject:

The actual fix is cleaning the carbon out of the combustion chamber---you may be able to work around the problem by setting the idle lower---if all things are right in an engine I should be able to hold the throttle wide open and turn the key off and the engine should quit---if the ignition system cannot control the combustion in the engine there is a problem that needs to be addressed................Dan
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I don't think I have ever had a car that was "FINISHED"........unless it was totaled.