Over-revving and fast idle
09-22-2002, 03:28 PM
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Racer
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Over-revving and fast idle
Hi everyone.
I took my car out for its fortnightly "keep everything moving" run - and as soon as I fired it up I noticed it was idling too fast. In fact it was idling around 2,000 rpm instead of around 800. I thought it might be a choke problem so decided to see what happened as it warmed up.
As I drove the car I noticed that it wasn't just an idle problem - the car just seemed reluctant to lose revs. Anyway I got to my destination, switched it off, and tried pushing the throttle to see if anything felt stiff. It felt fine, and this time when I started it up the revs at idle rose to 2,500. I switched it off again and disconnected the battery fo a few minutes to see if that would help. It didn't.
I was starting to get worried now, but I thought I'd try one more thing. I remember a mechanic telling me that quite often 911s that weren't driven hard for a while developed rough running problems. So I drove it flat out on the way home, redlining it in every gear. And guess what? The problem went away.
So - should I be worried? Or do I just need it to work it a bit harder when I take it out??
I took my car out for its fortnightly "keep everything moving" run - and as soon as I fired it up I noticed it was idling too fast. In fact it was idling around 2,000 rpm instead of around 800. I thought it might be a choke problem so decided to see what happened as it warmed up.
As I drove the car I noticed that it wasn't just an idle problem - the car just seemed reluctant to lose revs. Anyway I got to my destination, switched it off, and tried pushing the throttle to see if anything felt stiff. It felt fine, and this time when I started it up the revs at idle rose to 2,500. I switched it off again and disconnected the battery fo a few minutes to see if that would help. It didn't.
I was starting to get worried now, but I thought I'd try one more thing. I remember a mechanic telling me that quite often 911s that weren't driven hard for a while developed rough running problems. So I drove it flat out on the way home, redlining it in every gear. And guess what? The problem went away.
So - should I be worried? Or do I just need it to work it a bit harder when I take it out??
09-23-2002, 08:28 AM
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Drifting
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Greg
is this the turbo that you've been 'selling' for a while - or is that just a cover story for your other half
Maybe you should drive it more thanonece a fortnight!!
Anyway, maybe the idle microswitch needs a look at - though I'm sure Adrian or someone can give you some proper advice once they see this thread.
Bye.
is this the turbo that you've been 'selling' for a while - or is that just a cover story for your other half
Maybe you should drive it more thanonece a fortnight!!
Anyway, maybe the idle microswitch needs a look at - though I'm sure Adrian or someone can give you some proper advice once they see this thread.
Bye.
09-23-2002, 08:48 AM
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Dear John,
The Turbo uses the CIS (continuous injection system). It uses two control units for ignition and the other for acceleration. I am afraid my knowledge on these engine control systems is very limited. I will know more when I have got further into my 911SC book.
So I am afraid I am not much help. Mind you from Gregs post I would suspect the problem is diretly related to lack of use and is mechanical in nature rather than electronic.
Ciao,
Adrian
911C4
The Turbo uses the CIS (continuous injection system). It uses two control units for ignition and the other for acceleration. I am afraid my knowledge on these engine control systems is very limited. I will know more when I have got further into my 911SC book.
So I am afraid I am not much help. Mind you from Gregs post I would suspect the problem is diretly related to lack of use and is mechanical in nature rather than electronic.
Ciao,
Adrian
911C4
09-23-2002, 02:02 PM
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Racer
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The car is definitely for sale 
Definitely, really, advertised in Top Marques.
That's why I take it out so rarely - sod's law dictates that the moment you commit to selling a car, that's when it gets dinged. So I'm being cautious.
Ah well. Good job it wasn't a test drive. I'll still only take it out once a fortnight, but just drive it harder when I do.
Definitely, really, advertised in Top Marques.
That's why I take it out so rarely - sod's law dictates that the moment you commit to selling a car, that's when it gets dinged. So I'm being cautious.
Ah well. Good job it wasn't a test drive. I'll still only take it out once a fortnight, but just drive it harder when I do.
10-01-2002, 09:03 AM
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Burning Brakes
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Hi Greg
Try pinching the hose at right side of the intercooler connected to a shiny object below the IC, when the engine is warm (very important).
If they idle goes down your cold start regulator is most probably gone.
Report back and I will explain how you can test your cold start regulator.
Adrian, I might have send you a text describing this problem....
Good luck
Staffan
Try pinching the hose at right side of the intercooler connected to a shiny object below the IC, when the engine is warm (very important).
If they idle goes down your cold start regulator is most probably gone.
Report back and I will explain how you can test your cold start regulator.
Adrian, I might have send you a text describing this problem....
Good luck
Staffan
10-01-2002, 09:09 AM
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Burning Brakes
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Sorry, didn't read the whole post, the problem is gone. <img src="graemlins/c.gif" border="0" alt="[ouch]" />
Still, you might have a problem with the cold start regulator. If you get the problem again, follow the instructions above.
Damn, could't bash Adrian for not using my text
Staffan
Still, you might have a problem with the cold start regulator. If you get the problem again, follow the instructions above.
Damn, could't bash Adrian for not using my text
Staffan
