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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
  • 1994 - 1995 Specific Tech

Why is my car doing this?

  • Thread starter Thread starter laserstang94
  • Start date Start date Mar 11, 2006
L

laserstang94

New Member
Dec 20, 2005
18
0
1
Mar 11, 2006
#1
  • Mar 11, 2006
  • #1
I have a 94 gt and cant find out why it is revving so high at idle 1200 to 1300. I checked for vacuum leaks and I dont have any. Can anyone tell me what is going on here......

mods:
cold intake
equal length headers
gt40 intake with ported lower
msd billet aluminum distributor
msd ignition coil
2 chamber exhaust
off road h-pipe
power pulleys
110lph fuel pump
stock injectors
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 12, 2006
#2
  • Mar 12, 2006
  • #2
Congrats on the first official [Tech] post.

More info would be helpful. What is your normal hot idle? Any recent work? Did this just happen one day or has it been gradual?
Does it idle down like it has a vac leak?

More info will help.

What happens to the idle when you disconnect the IAC?

Good luck.
 
L

laserstang94

New Member
Dec 20, 2005
18
0
1
Mar 12, 2006
#3
  • Mar 12, 2006
  • #3
it happened after i installed the intake manifold..........
 

Guero

Active Member
Oct 11, 2005
2,148
0
47
Mar 12, 2006
#4
  • Mar 12, 2006
  • #4
HISSIN50 said:
What happens to the idle when you disconnect the IAC?

Good luck.
Click to expand...
my idle goes lower but stays low. what does that mean. sorry for hijacking
 

mo_dingo

20+ Year Stangneter
Aug 26, 2003
3,031
2
58
Tucson, AZ
Mar 12, 2006
#5
  • Mar 12, 2006
  • #5
laserstang94 said:
it happened after i installed the intake manifold..........
Click to expand...

Sounds like a vacuum leak at the intake, or a line has broken....Get a vacuum gauge and see how many inches of vacuum it's pulling at idle. You could be missing something.

spraying carb cleaner around the base of the lower intake, where it meets the heads, should show you if something didn't seal right.

Did you R&R the IAC valve, or did you just leave it on?
Scott
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Mar 13, 2006
#6
  • Mar 13, 2006
  • #6
If you dont mind removing all the vac lines and sealing the intake, you can do it but put a vac gauge on one fitting. Disable the ignition/fuel system and crank the motor. Look for 3-8" hg on your gauge. Less suggests a leak.

Guero, If this was done on a hot motor, it means your IAC works but you set your idle differently than I do.

Good luck to both.
 
L

laserstang94

New Member
Dec 20, 2005
18
0
1
Mar 13, 2006
#7
  • Mar 13, 2006
  • #7
mo_dingo said:
Sounds like a vacuum leak at the intake, or a line has broken....Get a vacuum gauge and see how many inches of vacuum it's pulling at idle. You could be missing something.

spraying carb cleaner around the base of the lower intake, where it meets the heads, should show you if something didn't seal right.

Did you R&R the IAC valve, or did you just leave it on?
Scott
Click to expand...

you were right.....! that fixed the problem. one of my heated hoses were bad. thanks!
 
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