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When clutch released, engines revs up, HELP

  • Thread starter Thread starter BadLX5.0
  • Start date Start date Oct 30, 2005
B

BadLX5.0

New Member
Oct 30, 2005
4
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Oct 30, 2005
#1
  • Oct 30, 2005
  • #1
Hello, I just got a 89 LX and I put a known good 5.0 engine and tremec TKO 600 in it. I went to fire it up for the first time today and it runs fine with the clutch in. It idles, revs, but as soon as i let the clutch out a little bit the motor revs up to like 3500 rpm and stays there and will not come back down. Push the clutch back in, and its fine. I know there is two switches on the clutch pedal, and they go to the computer. When unplugged the car will not crank. Is it a switch problem? Or something else? Please HELP! I need to get this car on the road!! Any help, advice would be great! Thanks!
 

85_SS_302_Coupe

it sucks (I know) to be on the receiving end
15 Year Member
Nov 11, 2003
6,945
1,598
223
Northern KY
Oct 30, 2005
#2
  • Oct 30, 2005
  • #2
The switch is just the clutch safety switch...it's doing it's job....it's there to keep you from starting the car while it's still in gear (push the clutch in and it starts..)

As for the RPM thing, that's a new one for me...give it a few hours for everyone to get up and at'em and you'll get a good response.
 

Realmongo

I prefer to be called "Evil Genius"
Founding Member
Oct 10, 2001
2,468
86
99
Western Mass
Oct 30, 2005
#3
  • Oct 30, 2005
  • #3
Is your clutch cable or linkage interfering with your throttle cable/linkage either under the dash or in the engine compartment?
 
B

BadLX5.0

New Member
Oct 30, 2005
4
0
0
Oct 30, 2005
#4
  • Oct 30, 2005
  • #4
The engine cable and clutch cable are clear of eachother. When I release the clutch, if someone else is watching the engine cable, it doesnt move. THe IAC or something else is making the engine rev up I think, but I have no idea why....
 

Ny Mustang Guy

Founding Member
Dec 10, 2001
322
0
0
Queens Nyc
Oct 30, 2005
#5
  • Oct 30, 2005
  • #5
Have you brought it on the road yet? If you were driving on the road, left it in gear and let go of the gas while its moving in gear, would the car basically "drive itself" meaning you dont have to press the gas to get going (as if the gas is still being pressed)?
 

1991vert

10 Year Member
Feb 27, 2004
1,103
7
69
Ludlow, MA
Oct 30, 2005
#6
  • Oct 30, 2005
  • #6
my vote is IAC. with the clutch coming out, your car doesnt think it's idling anymore.

just my $0.02
 
B

BadLX5.0

New Member
Oct 30, 2005
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Oct 30, 2005
#7
  • Oct 30, 2005
  • #7
It hasnt been driven down the road yet. Seems kinda dangerous.. THe IAC is new, it worked on the last car, i guess that doesnt mean its good though.
 
J

jmd2914

Founding Member
Sep 6, 2002
937
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0
Napa, California
Oct 30, 2005
#8
  • Oct 30, 2005
  • #8
my car did that and it was the IAC, but its starting to do it again, i think i need a new one.
 
B

BadLX5.0

New Member
Oct 30, 2005
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0
Oct 30, 2005
#9
  • Oct 30, 2005
  • #9
Hmm.. It worked before but I guess things fail.. I thinks its just weird that it acts up with the clutch pedel. With the clutch in it idles and runs fine. IM gonna try unplugging it to see if it does it then. Any more suggestions? THanks
 
R

RoadconeTuning

New Member
Apr 4, 2006
458
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0
Upstate, SC
Apr 18, 2006
#10
  • Apr 18, 2006
  • #10
my friends focus did this and he just took his IAC out and cleaned it w/ alcohol every few months.
 
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