Tj Sahara 4.0 auto-high idle

D Mann

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Leland, NC
Need some help from the younger experts. I have a 2001 Wrangler Sahara 4litre auto.
I cleaned the throttle body, replaced the MAP, IAC, TPS, coil pack, spark plugs , air filter, both PCVs. At start up, it is perfect, idles great sounds good. After a drive just a very short distance , the idle shoots up to over 2000rpms. Where do I look? Can someone(s) help me, please? I'm a 66yo novice.Just reconnected the battery, and started it again. It idled perfectly. When I revved it up once, it stay high about 1200rpm. It would not come down. Help, please.
 
Need some help from the younger experts. I have a 2001 Wrangler Sahara 4litre auto.
I cleaned the throttle body, replaced the MAP, IAC, TPS, coil pack, spark plugs , air filter, both PCVs. At start up, it is perfect, idles great sounds good. After a drive just a very short distance , the idle shoots up to over 2000rpms. Where do I look? Can someone(s) help me, please? I'm a 66yo novice.Just reconnected the battery, and started it again. It idled perfectly. When I revved it up once, it stay high about 1200rpm. It would not come down. Help, please.

Was it behaving this way before you replaced all of the above or is this new behavior? New parts doesn't necessarily mean good parts, your new iac for example, what brand did you purchase?
 
Was it behaving this way before you replaced all of the above or is this new behavior? New parts doesn't necessarily mean good parts, your new iac for example, what brand did you purchase?

It started with the TPS. Engine died driving down the road and threw a code for the TPS. I replaced it (Duralast) and started right up. I then replaced the IAC, and MAP. It has always idled a little high, but now, it's between 1200 and 2000. I did replaced the valve cover gasket a few days earlier but don't see a correlation there.
 
If you have your old IAC you could swap it back on and see if that changes the idle behavior and will tell you whether the new IAC is part of the problem.

You should check for vacuum leaks also.
 
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