1997 Jeep Laredo Engine RPM drops, then revs quickly or sim

1997 JEEP GRAND CHEROKEE LAREDO
200,000 MILES • V8 • 2WD • AUTOMATIC
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ELLEN58
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We have replaced the TPS and MAP sensors trying to cure this problem with no success. When driving continuously , the Jeep runs like a dream, but if you must slow down (as in rush hour traffic) or if you must stop at a stop sign or a traffic light the RPMs will drop very low, then rev the engine quickly, causing the Jeep to try to lerch forward (you MUST keep your foot strongly on the brake or it will plow someone ahead of you in the rearend !!!) or it will not rev back up, and it will simply die. Any suggestions ??? I love my Jeep, but it is becoming very dangerous to drive due to this problem. Any suggestions for a cure would be greatly appreciated.

Thanks.
Oct 5, 2009 at 7:17 PM
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JACOBANDNICKOLAS
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HAs the check engine light come on?
Nov 9, 2009 at 10:28 AM
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ELLEN58
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[quote:8bbb70674d="Jacobandnickolas"]HAs the check engine light come on?[/quote:8bbb70674d]

It stays on most of the time....this is due to the fact that an oxygen sensor just behind the engine...located on the exhaust pipe...on the passenger side of my vehicle was cut off by one of its previous owners when they removed the catalytic converter. I have now replaced all 3 sensors where the MAP sensor is located. I think they were the TPS, the MAP, and the ??? can't remember right off hand what the other one was called, but they are all 3 located on top of the engine, together....still, no success. Problem is no better.
Nov 9, 2009 at 2:11 PM
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JACOBANDNICKOLAS
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If the light has been on, have you had the computer scanned? Most auto parts stores will do it for free. Also, has the O2 sensor that was cut because of the converter that was removed ever been replaced?
Nov 9, 2009 at 7:36 PM
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