Rough Idle, Idle Speed Variation, Quits on braking when warm

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POOLBABE
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  • 1 POST
1994 Jeep Grand Cherokee Ltd, 147,000 miles, V8 (5.2 liter), Auto, 4 WD

I am a female owner who works on my own vehicles. Cannot afford to take vehicle to mechanic. I drive it a few times a week. Jeep started out idling very rough for a couple of weeks. Then died when braking after engine warmed up. Repeatedly died upon immediate restart. Checked spark plugs. One was covered in gas. One cyl not working. Rest of plugs perfect. Dried off wet plug. Changed out all plug wires. Distrib looks ok. Changed air filter. Idled slightly better but still rough. Runs ok when cold but still dies when braking after engine warms up. Have yet to check trouble codes. In the meantime, would really appreciate any input and suggestions.
Jul 25, 2007 at 10:30 AM
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MERLIN2021
  • ✓Experienced Mechanic
  • 17,250 POSTS
If a plug was wet, you need to fix the no fire condition at that cylinder! Check for spark by using an old plug. after you do this get back to me...
Jul 30, 2007 at 9:08 AM
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SLOFING
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  • 21 POSTS
Sounds like you may also have a ruptured brake booster, if the master is leaking fluid into the booster when you apply the brakes, it will go into the intake. Is the vacuum hose in the general area of the fouling plug?
Jul 30, 2007 at 9:35 AM
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