Oscillating idle on deceleration
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Joined: Nov 2010
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From: Pooler GA
Oscillating idle on deceleration
Just bought a '61 315 about two months ago. When I start the car the car idle fines. Recently, when the engine decelerates as I approach a stop and I disengage the clutch the engine oscillates, revving between 1500 to 2000 RPM’s and 500, increasging to 2,500 or 3,000 then to 0, to the point that it just shuts down. It starts right back and it idles ok when I restart the car.
Anyone have any ideas what is going on?
Thanks for your help.
Lou
Anyone have any ideas what is going on?
Thanks for your help.
Lou
Drifting
Joined: Jun 2007
Posts: 1,640
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From: DeBary Fl. Amateur Radio Operator K3CQR
1st thought Lou, is the throttle returning to closed? Possible weak or incorrect return spring. Bill. PS, if you get a chance, fill in your profile.
Last edited by Bill Irwin; Dec 2, 2010 at 07:13 PM.
Race Director
Joined: Feb 2007
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From: northern california
C2 of Year Finalist (track prepared) 2019
The fact that the engine dies strongly suggests [to me] that it's not getting fuel. If the FI unit still has its original spill valve, this valve could be sticking open..... which diverts fuel back to the bowl and away from the nozzles.
What do you know about the history of the fuel injection? How recently was it rebuilt? When it was rebuilt was a more modern "thumb tack" style spill valve installed or does it retain its [possibly misnamed] "good guy" spill valve?
Jim
What do you know about the history of the fuel injection? How recently was it rebuilt? When it was rebuilt was a more modern "thumb tack" style spill valve installed or does it retain its [possibly misnamed] "good guy" spill valve?
Jim
Le Mans Master
Joined: Sep 2009
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From: "You may all go to Hell- and I will go to Texas- Davy Crockett
St. Jude Donor '12
Just bought a '61 315 about two months ago. When I start the car the car idle fines. Recently, when the engine decelerates as I approach a stop and I disengage the clutch the engine oscillates, revving between 1500 to 2000 RPM’s and 500, increasging to 2,500 or 3,000 then to 0, to the point that it just shuts down. It starts right back and it idles ok when I restart the car.
Anyone have any ideas what is going on?
Thanks for your help.
Lou
Anyone have any ideas what is going on?
Thanks for your help.
Lou
Race Director
Joined: Feb 2007
Posts: 15,491
Likes: 8,963
From: northern california
C2 of Year Finalist (track prepared) 2019
Le Mans Master
Joined: Sep 2009
Posts: 9,151
Likes: 481
From: "You may all go to Hell- and I will go to Texas- Davy Crockett
St. Jude Donor '12
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