RPM's hanging

What's up everybody. I got a question. I have an 08 2.7L 5 speed manual. OK, say i'm on the freeway going about 75 and I throw the truck into neutral. Normally the rpms drop. However, sometimes they stay at around 2800-3000 even with the truck in neutral. I have to rev it to redline just to get them to drop.

This has happened before in the past, but than went away. My truck has 93,000 miles. I purchased the 100,000 warranty and will be taking the truck in to the dealer. Does anyone else have this kind of problem?

 

I'm definitely not a mechanic, but I'll throw out some simple things to consider first: Throttle body requires cleaning, loose electrical connection on the throttle body, PCV valve clogged, a vacuum leak somewhere, air filter requires cleaning/replacement, MAF sensor dirty, intake ducting not fully connected or clamps not tightened . . . I'm thinking fuel and/or air related. Does your truck fall under the stuck gas pedal recall? Start simple then move up to the more expensive/involved things.

 

stuff to check first:

1) clean MAF
2) clean throttle body and IAC
3) inspect for vacuum leaks
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reset ecu, test
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problem continues...

possibly
4) replace TPS or at least check it's values (these are cheap items to replace,
and they are critical for engine management...but they wear down over time and
provide inaccurate readings...)

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reset ecu after any item is cleaned, replaced, or leak fixed
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Thank you guys for your quick and very helpful insight. I have a K&N drop in. I am always afraid that I am over oiling the filter when I clean it. Could the oil from that be messing up the MAF? I am going to be checking into all these suggestions, thanks!

 

YES!

4 usual things mess up the MAF

1) vapors from the PCV valve making their way back up the
intake after engine shutoff, and depositing on the MAF wires

2) any random chunk of mung or dirt that might make it's way in

3) oil from an oiled filter

4) disturbing the airflow by deviating from factory specifications
(CAI's for example) and the MAF simply doesn't get the correct airflow
around it to produce accurate readings