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RPMs will not drop

  • Thread starter Thread starter nero6
  • Start date Start date May 1, 2010

nero6

Member
Aug 30, 2007
94
0
6
May 1, 2010
#1
  • May 1, 2010
  • #1
I just finished replacing my intake gaskets along with installing new headers. At the same time I cleaned my MAF sensor which was full of gunk. I start it up and have some idle issues with the rpms surging up and down. So I fixed that by following the idle reset procedure. I still have a high idle (about 1100 rpm) but it is smooth. My biggest concern is when I give it a shot of gas while ideling, the RPMs go up and when I release the gas the come down part way but then stick at 2500 RPM for 5 or more seconds before returning back to 1100 rpm. Also when I first start up the car the RPMs shoot up to a little over 3000 rpms and hang there for a few seconds before settling out at 1100 RPM. Any thoughts on what the cause could be. I checked the throttle plate operation and it is smooth and not binding on anything. Would really like to finally get it out on the road for the season, any help would be greatly apreciated!
 

KENS89LX

Member
Mar 12, 2006
302
1
19
Cross lanes Wv
May 3, 2010
#2
  • May 3, 2010
  • #2
Sounds like a vacuum leak to me, check those if you havent already. The idle reset procedure? does that mean you reset the computer?
 

nero6

Member
Aug 30, 2007
94
0
6
May 3, 2010
#3
  • May 3, 2010
  • #3
my89blubyu said:
Sounds like a vacuum leak to me, check those if you havent already. The idle reset procedure? does that mean you reset the computer?
Click to expand...

Ya, a vacuum leak was my first thoght as well. Nothing that I can see so far though. Yes I did reset the computer. The car seems to run much better when I disconnect the IAC while doing the idle reset steps so I am now leaning towards a bad IAC if I can't locate a vacuum leak. I also pulled the KOEO codes and did not come up with anything either.
 
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