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  • 1996 - 2004 SN95 Mustang -General/Talk-
  • SN95 4.6L Mustang Tech

RPM'S Are Doing More Than Hanging

  • Thread starter Thread starter bigblackboat
  • Start date Start date Dec 6, 2004

bigblackboat

New Member
Mar 1, 2004
43
0
0
Langhorne, Pa.
Dec 6, 2004
#1
  • Dec 6, 2004
  • #1
My car, now instead of just the hanging rpms, jumps about 200rpms everytime I take her out of gear. The rpms jump, hang, and then slowly drop. I know mustangs are notorious for the hanging rpms and i've experienced it from day one, but now they jump! WHAT IS THAT? Does anyone else experience this? Is the egr valve or something else going bad and need to be replaced? Oh yeah, I noticed my mpg went down the toilet also since she had this problem. Can anyone help me? Thank You!
 

GetImpact

New Member
Nov 6, 2003
89
0
0
MD
Dec 6, 2004
#2
  • Dec 6, 2004
  • #2
I had a similar... but much more severe... rise and hang problem with an '02 SVT Focus. Started around 10K miles shortly after a computer reflash done by Ford. It would rise to somewhere between 3K and 4.5K RPMs and totally stick or fall off slowly after several seconds, but only when warmed up. Really hard to shift like that in traffic, and I told the dealership there was no way the clutch wouldn't die early from such a lack of throttle control... that they'd better be willing to replace that under warranty if the problem continued. Of course, they balked at the idea (wear item, you know).

By the time I got rid of it (so many other problems too) we were starting to focus our attention more and more on the Idle Air Control and/or the new computer program or maybe a combination of the two. Several times at the dealer chasing it down (the last time almost a week) and they never managed to get it totally under control, but it got a little better after an IAC replacement.

Maybe start there.

I sure hope you have more luck with this sort of thing than I did. What a gremlin that was. I ended up dumping that Focus back on Ford to get a new Mustang. A long, painful story, but the 'Stang has not had any real problems so far.
 

Stork_

New Member
Aug 7, 2004
22
0
0
Dec 6, 2004
#3
  • Dec 6, 2004
  • #3
Did you recently mess with your Throttle body or plenum?
 

JonJon

Founding Member
Aug 16, 2002
4,801
1
68
back in Marylands
Dec 6, 2004
#4
  • Dec 6, 2004
  • #4
Mine does that. it's annoying.
 

bigblackboat

New Member
Mar 1, 2004
43
0
0
Langhorne, Pa.
Dec 6, 2004
#5
  • Dec 6, 2004
  • #5
I recently reinstalled my cai back back through the fender with the rotated maf. I had it like a straight shot before. I also put an oil breather cap on, but that was like 2 months ago. I noticed this rpm thing about a week ago. Other than that, nothing!
 

bigblackboat

New Member
Mar 1, 2004
43
0
0
Langhorne, Pa.
Dec 7, 2004
#6
  • Dec 7, 2004
  • #6
My idle is alittle loopy too. Not real bad but slightly. But I think that is from the rotated maf and deleted maf screen. If the iac or egr valve was going bad, wouldn't it throw a code?
 

Blk01gt_

Founding Member
Sep 1, 2001
422
0
0
winnipeg, canada
Dec 7, 2004
#7
  • Dec 7, 2004
  • #7
my RPM's jump up by a couple hundred when i put the clutch in to shift too, but it has been like that since day one. I just thought it was normal
 

Stork_

New Member
Aug 7, 2004
22
0
0
Dec 8, 2004
#8
  • Dec 8, 2004
  • #8
Sounds to me like your MAF may need to be adjusted.
 
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