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-   -   Dies on throttle release (http://www.jeepforum.com/forum/f13/dies-throttle-release-1534269/)

pete99 06-09-2013 03:04 PM

Dies on throttle release
 
I recently replaced spark plugs, spark plug wires, rotor and cap, and installed new Accel Ignition Coil. It purrs like a kitten (technical description, idles nice and smooooth). When I blip the throttle it's fine, RPM increases good, but when I let go of the throttle, it stumbles really bad and almost dies. The idle manifold vacuum is 20 InHg at around 800 RPM. The only DTC is 55 as I disconnected the battery, no other codes. I am the original owner and only have 30,000 miles on it. Thanks for any suggestions!

vonericsen 06-09-2013 03:29 PM

If you disconnected the battery for longer than 20 minutes it's probably relearning the idle. Once it's done it should stop stumbling.

zj97ltd 06-09-2013 03:56 PM

If your battery is on its way out or connections are loose it can cause this too.

JasonStebbins 06-09-2013 04:46 PM

Original owner with 30,000 miles?! :eek:

Does it only do this when idling or when you are driving as well? Has it ever actually stalled?

Does it accelerate fine?

Check and make sure all the grounds are are clean and tight.

pete99 06-09-2013 05:26 PM

Dies on throttle release
 
Sorry, newbie here.
Yes, I know, only 30k miles. My work was only 4 miles away, so over 18 years or so, not much mileage. Trips to Moab, Tahoe, etc didn't add much.<g>
Idles and accels nicely. Just stumbles on throttle release. Engine died once, usually RPM drops to near zero then recovers. This is all inside garage. I drove it around block and it drives very good, accel and decel. Just don't know if I can trust it not to stall when slowing for light or stop sign, or have to get off throttle for some reason out on the road. Checked TPS, manifold Temp, and MAP sensors, all okay. Bought a Fuel Pressure gage and the fuel pressure read correctly. Battery has been maintained with charge maintainer and is in good shape. Vacuum is steady at idle (20 InhG). CORRECTION- The only error code on the CEL is 12 for battery disconnect, not 55. Thanks for any ideas....

JasonStebbins 06-09-2013 05:54 PM

Hmm, you've checked a lot of things I would have suggested. :laugh:

Have you checked all the grounds already?

ZeeJay1997 06-09-2013 07:11 PM

I nominate the IAC... clean it up and see how it does.

dusterdude 06-09-2013 07:11 PM

Clean iac and you may need a crank sensor

HurricaneRZA 06-09-2013 07:15 PM

Quote:

Originally Posted by ZeeJay1997 (Post 15540072)
I nominate the IAC... clean it up and see how it does.

x2

When I swapped my throttle body the IAC was acting up and I ended up having to idle manually until I cleaned and put back the original IAC

jnicewan 06-09-2013 11:17 PM

Quote:

Originally Posted by ZeeJay1997 (Post 15540072)
I nominate the IAC... clean it up and see how it does.

I bet this is it too, clean it and see what happens, also clean out the passage the IAC plunger goes into along with the throttle plate and bore. If you are picky about keeping parts replaced then buy a new one after you discover it was dirty or bad.

kachink 06-09-2013 11:55 PM

Quote:

Originally Posted by jnicewan (Post 15541096)
I bet this is it too, clean it and see what happens, also clean out the passage the IAC plunger goes into along with the throttle plate and bore. If you are picky about keeping parts replaced then buy a new one after you discover it was dirty or bad.

x2

Remove the throttle body and clean it throughly. If you remove it you can clean the entire IAC passage all the way through.

dnuccio 06-10-2013 12:10 AM

Quote:

Originally Posted by kachink (Post 15541204)
x2

Remove the throttle body and clean it throughly. If you remove it you can clean the entire IAC passage all the way through.

this^
mine ran so much better after i cleaned the TB

pete99 06-30-2013 03:08 PM

I removed and cleaned the TB and sensors. That seems to have fixed it! Thanks so much to all that provided input.


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