First drive for a while - engine idling up and down

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james
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Joined: Sun Jun 11, 2006 8:10 pm
Location: Scotland

First drive for a while - engine idling up and down

Post by james » Tue Sep 11, 2007 10:13 am

Got back from hols last night, drove to work, car has been sitting for 4 weeks apart from a short run two weeks ago. It barely started then the revs rose then fell rose then fell.

It drives "ok" but when in traffic the revs wont say still and its "jerky" and generally a pig.

The battery was almost flat but it DID start first time - although wierdly the lights went on by themselves after the engine fired up :?

Should I just charge the battery or is this the dreaded flow indicator thingamajig thats stuck through lack of use?

Any thoughts? what a shame, I was so looking forward to a good blast after such a long time away without the Elise.

Basically it idles from 1500 rpm to 2000 then back to 1500 then to 2000 and so on. Makes me look like a boy racer blipping the throttle and it doesnt seem to shut the throttle off when I lift off sometimes then other times its just too abrupt.

Drove fine last time I drove it.

:(
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Rich H
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Post by Rich H » Tue Sep 11, 2007 10:47 am

It's just the ECU trying to charge the battery. Drive it more :thumbsup
1994 Lotus Esprit S4 - Work in progress
1980 Porsche 924 Turbo - Funky Interior Spec
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james
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Post by james » Tue Sep 11, 2007 11:19 am

RICHARDHUMBLE wrote:It's just the ECU trying to charge the battery. Drive it more :thumbsup
Clever cars these! Hope the drive home is better. Thanks.
:)
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mac
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Post by mac » Tue Sep 11, 2007 11:29 am

It may also be the IACV re-learning the setting.

If it does it again from start up, leave the car alone and let it settle.

This will involved the car reving up and then almost stalling for a few cycles - once warm the revs should settle back to normal - or slightly increased if a low battery voltage is detected.

The important thing is to let it find it's own setting and not intervene with a dab of throttle.


Mac
S2 Elise (cobalt blue with stripes) - toy spec
Caterham 7 - hillclimb spec
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transglobal
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Post by transglobal » Tue Sep 11, 2007 11:50 am

Had the same a while back in my S1. Thought it was throttle body etc, etc. Turned out that it wasn't being driven enough. The more I drove it the better it got.

Also, give your throttle cable an oil or spray with a lub as I found that when the car had been sitting for a while it took an age to loosen up and caused the revs to rise and fall as you've described.
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james
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Post by james » Tue Sep 11, 2007 12:12 pm

Thanks guys, good job I normally use the car everyday. I will let it sit later so it works itself out.

Will get the spray lube out for the cables too.

8)
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james
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Post by james » Wed Sep 12, 2007 9:31 am

mac wrote:It may also be the IACV re-learning the setting.

If it does it again from start up, leave the car alone and let it settle.

Mac
Fired up this morning, all fine, drive to work back to normal. Guess its a bit like me - bit sleepy in the morning especially after a holiday 8)
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