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Throttle Sticking??

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Old 11-13-2022, 06:27 PM
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Exclamation Throttle Sticking??

Hello Everyone, new guy here. Bought myself an 87 Cherokee 2 door last week. Have a few problems, but overall shes a runner! One thing thats puzzling me right now.. I was up in some snow yesterday, got on it going up a hill, 4Wd popped out, had to back down. Still has the stock vacuum 4wd set up, so i think ill just get rid of that.. After this about 5 mins, my idle wouldnt come down from 2000-2500. Stopped popped the hood, pulled on the throttle cable and it was returned all the way back to the idle postion, but the engine was still revved. what is causing this?
Old 11-14-2022, 06:03 AM
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Since it's an 87, you need to visit www.cruiser54.com and complete Tips 1 through 5.
Make sure your intake manifold bolts are snug also.
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Old 11-14-2022, 08:56 AM
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Vac line to the disconnect still attached?
Old 11-14-2022, 04:10 PM
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To what disconnect would that be?
Old 11-14-2022, 04:41 PM
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Originally Posted by 5fingerfuller
To what disconnect would that be?
CAD STINKS


The big issue is that the CAD system only fails when you need it the most.

Kinda like when you don't realize your wiper blades need replacing until it rains....

I know somebody’s system works and he advocates keeping it stock, but my exposure to the failures is probably hundreds of times greater than his, as a result of being Service Manager at a Jeep dealership from 1980 through 1992, and being a current XJ and MJ owner.

CAD stinks. Every Jeep I work on with it, I eliminate it. Guess what I find in the process? 25 year old busted vacuum lines, bloated vacuum line connectors, bad vacuum reservoirs and piping, bad transfer case vacuum switches. In other words, had the person gotten into a sticky situation and needed 4WD, they would have been screwed!!!

That's the tip of the iceberg. The factory went through 3 revisions of the shift fork also. The fork issue is non-existent if you just slide it over and leave it.

See the link below for complete instructions. Takes less than 1/2 hour.

https://www.cherokeeforum.com/f51/fre...ss-91-a-38629/
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Old 11-14-2022, 06:28 PM
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Originally Posted by cruiser54
CAD STINKS


The big issue is that the CAD system only fails when you need it the most.

Kinda like when you don't realize your wiper blades need replacing until it rains....

I know somebody’s system works and he advocates keeping it stock, but my exposure to the failures is probably hundreds of times greater than his, as a result of being Service Manager at a Jeep dealership from 1980 through 1992, and being a current XJ and MJ owner.

CAD stinks. Every Jeep I work on with it, I eliminate it. Guess what I find in the process? 25 year old busted vacuum lines, bloated vacuum line connectors, bad vacuum reservoirs and piping, bad transfer case vacuum switches. In other words, had the person gotten into a sticky situation and needed 4WD, they would have been screwed!!!

That's the tip of the iceberg. The factory went through 3 revisions of the shift fork also. The fork issue is non-existent if you just slide it over and leave it.

See the link below for complete instructions. Takes less than 1/2 hour.

https://www.cherokeeforum.com/f51/fre...ss-91-a-38629/
,
I plan on doing this Thursday night, wasn’t to worries about that part! Thanks for the link though that will be great help. You guys are awesome. Going to go through that list one by one and get her running top notch. I still have been driving it every day. Took it a few places yesterday I wouldn’t take any of my other vehicles so I’m plenty happy!
Old 11-14-2022, 07:43 PM
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we'll get it all sorted out.
Old 11-14-2022, 08:11 PM
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Originally Posted by 5fingerfuller
After this about 5 mins, my idle wouldnt come down from 2000-2500. Stopped popped the hood, pulled on the throttle cable and it was returned all the way back to the idle postion, but the engine was still revved. what is causing this?
check the throttle body butterfly plate as the bushes are known to wear, and cause the butterfly valve not to fully close, jam , or have freeplay

there is a Youtube video on repairing them, if that turns out to be an issue
Old 11-14-2022, 09:06 PM
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Hell, just clean the throttle body!!
Old 11-15-2022, 08:22 AM
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Nah that's a bit crazy
Old 11-15-2022, 08:47 PM
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Yeah. Stay away from that maintenance crap. Bites you in the *** every time.
Old 11-18-2022, 12:43 AM
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Default Step 1 complete.

Tonight I got some time to do a few things. Got rid of the CAD system. I plugged off the vac lines, that’s fine isn’t it? Also cleaned the throttle body, it seems the little brass/gold arm that’s on the firewall side is still sticky. Not sure what that’s about. Also went through all the grounds in step 1. Gonna go get that Napa part for the engine block to the fire wall tomorrow. Bumper and winch show up tomorrow as well!
Old 11-18-2022, 06:00 AM
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Great progress.

Where did you plug off the vacuum?

This may help:

Old 11-18-2022, 08:21 AM
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I plugged the three holes in the axle shift motor, then took out the little connector, and plugged the three holes against the frame.
Old 11-18-2022, 05:50 PM
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If it were me, I would block off the vacuum SOURCE to that system.


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