Idle problem

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Howie
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Idle problem

Post by Howie »

Hi ,
My Interceptor 111, with 440 engine, has recently developed an issue with its idle when in drive or park with my foot on the brake. If my car is stationary for any reason and in neutral or park the idle speed remains very constant at about 800 rpm, however if I put the car in to drive or reverse and hold it on the footbrake the idle speed becomes very erratic to the extent that it will eventually stall, I can easily stop this happening by putting it back into neutral, I would however like to know what causes this so any ideas would be welcome. I recently had the car on a rolling road so the timing was checked and all appeared well when tested. I have an Eadlebrook carburettor.
Thanks
Howie
Interceptor Mk111
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Frank Schwartz
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Re: Idle problem

Post by Frank Schwartz »

Vacuum leak ????? :?:
Frank
1973 MKIII Interceptor
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Steve Payne
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Re: Idle problem

Post by Steve Payne »

It could be a bit lean at idle, when on the rolling road did they fiddle with the mixture screws? These engines like running a little rich at idle.

Are you sure your rev counter is accurate? I have seen some of these rev counters out by as much 150rpm at idle.

Steve
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slotcarone
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Re: Idle problem

Post by slotcarone »

First a few questions. How old is the carburetor? Was it running fine and then it started doing the stalling in gear? How long since a tune up? Is the car still driving well except for the idle problem?
1972 Interceptor III
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Howie
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Re: Idle problem

Post by Howie »

Thanks for the replies.
The car runs fine as soon as I get going, it’s only happening when stationary. Once the car has warmed up the idle fluctuation just gets bigger until it hits zero and engine stalls. Carburettor is only a couple of years old and not done many miles. On the rolling road they did say it was running a bit rich and made a small adjustment. Any more ideas guys?
Thanks
Howie
Interceptor Mk111
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Steve Payne
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Re: Idle problem

Post by Steve Payne »

I think you have answered your own question, if it was running fine when it was ''running a little rich'' I would suggest you richen it back up again.

Steve
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colin7673
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Re: Idle problem

Post by colin7673 »

I had our car on a 'Rolling Road' a short time ago, it ran well for a while then started 'pinking' on checking the time it was 5 degrees out, had this all set up again, then adjust the carb as it was kicking out black smoke on kick down, now running as it should.. I think if you to go on a rolling road you really need someone who know these engines.

I wouldn't go back to the local one I have just used, but would be back to John Sleath again, but a little to far away.

http://john-sleath.com/index.htm" onclick="window.open(this.href);return false;

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slotcarone
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Re: Idle problem

Post by slotcarone »

Check the four bolts that hold the carb on to make sure they are snug. Do not overtighten. Sounds like either the idle speed is too low or maybe the idle mixture screws need adjustment. Hard to diagnose with being there and actually seeing what is happening.
1972 Interceptor III
133-5612
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