RPMs increase when coming to a stop

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ShawnQ
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Joined: Wed Feb 06, 2013 4:09 pm
Location: Bayou Vista, TX (Galveston area)

RPMs increase when coming to a stop

Post by ShawnQ »

When I come to a stoplight and am completely stopped, my engine revs to the point where I need almost all of my brake pedal to keep it still.

It doesn't happen every time. Seems to be after a long idle speed or after coasting in gear for a while. Is this a symptom of running too rich?

Any ideas?

Thanks
Shawn
1988 Grand Wagoneer, , 6" on 33x12.5 BFG M/Ts & Mickey Thompson Classic wheels
Currently undergoing a 5.3/6L80E/NP241C swap!
You can view my Build/Work In Progress thread by clicking HERE!

AwesomeJ10
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Re: RPMs increase when coming to a stop

Post by AwesomeJ10 »

Could be lean....

But I think it's the throttle cable. They are notorious for sticking.
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Stuka
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Re: RPMs increase when coming to a stop

Post by Stuka »

Could very well be a throttle issue. Do you have your brake depressed while this happens? Its possible your brake booster has a vacuum leak, combined with running rich, which would make your idle climb.
2017 JKU Rubicon
Pevious Jeeps: 1981 J10, 1975 Cherokee, 2008 JK, 2005 KJ, 1989 XJ

Topic author
ShawnQ
Posts: 355
Joined: Wed Feb 06, 2013 4:09 pm
Location: Bayou Vista, TX (Galveston area)

Re: RPMs increase when coming to a stop

Post by ShawnQ »

I found it guys.

My choke is disconnected, but I had manually set it to start the engine for the first time after replacing top end gaskets.

I never opened the choke back up... doh!

Opened it up and all is well now.

Thanks
Shawn
1988 Grand Wagoneer, , 6" on 33x12.5 BFG M/Ts & Mickey Thompson Classic wheels
Currently undergoing a 5.3/6L80E/NP241C swap!
You can view my Build/Work In Progress thread by clicking HERE!
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fulsizjeep
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Re: RPMs increase when coming to a stop

Post by fulsizjeep »

TeeHee! Awesome.

I was having choke challenges on Phoebe and discovered this week I had not lined up the choke linkage in the right place for the coil in the choke stove. Still need to richen the setting more but it's working.
Flint Boardman
88 GW, 401/727/208, 5" lift, D44s/4.10s/locked up, 35s
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AwesomeJ10
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Joined: Sat Aug 27, 2011 10:26 am
Location: Off the grid on Storm Mountain Colorado
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Re: RPMs increase when coming to a stop

Post by AwesomeJ10 »

What is a choke? :?:
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