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FMS 65TB Now High Idle

  • Thread starter Thread starter 95GTV8
  • Start date Start date Jan 16, 2006

95GTV8

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Jul 25, 2005
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Jan 16, 2006
#1
  • Jan 16, 2006
  • #1
I just put on a FMS 65mm tb, and now i have a high idle, when i turn the car on it turns on fine, and it idles round 1200, but when im driving let's say 60mph and i put it in neutral the idle stays around 1500 rpm, the slower im moving in neutral the lower the idle goes, is it just a simple turn of the idle screw down to fix my idle problem, or is their another underlying issue?
 

srothfuss

Last night I stabbed the same guy 7 times in a row
Oct 17, 2004
1,796
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Woodward Ave.
Jan 16, 2006
#2
  • Jan 16, 2006
  • #2
The VSS is designed to keep the idle up a little higher while moving down the road.

Your base idle probably needs to be adjusted a little. Try searching for tips on how to set your base idle.
 

95GTV8

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#3
  • Jan 16, 2006
  • #3
allright, i know how to reset my base idle, when i turn the car on and im not moving it idles around 1k which is fine, but if im going down the road fast, and i put it in neutral the idle is around ~1300, with my old TB, if i did the same thing the idle would go back down to 900, is it just the base idle difference in the throttle bodies which is causing this? or is their something else dif in the tb's.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jan 16, 2006
#4
  • Jan 16, 2006
  • #4
Does the new TB have a hole in the butterfly?

You have two means of adjusting the idle on your 95 - the idle stop screw and the IAC bleed adjuster. I have been farting around with the adjustments myself. You could try running the bleed back in a little if the idle hangs ever so slightly while stationary and revving (the VSS input will exacerbate the issue).

This is pretty common for SN95s. A member named R.J. (that is his username) just made a batch of idle plates and mailed them to stangers for testing. Some people who had hanging idles after HCI's report that the plate can help (you could make the plate pretty easily).

Good luck.
 

95GTV8

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#5
  • Jan 16, 2006
  • #5
what exactly is the butterfly? I know of the base idle screw, what is the iac bleed control?
 

18mustangs

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Jun 8, 2005
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Virginia Beach, VA
Jan 16, 2006
#6
  • Jan 16, 2006
  • #6
95GTV8 said:
what exactly is the butterfly? I know of the base idle screw, what is the iac bleed control?
Click to expand...

Did you clear the computer before installing the TB. Sometimes when you're replacing things it helps to disconnect the batter for 30 minutes before starting the car again.
Tim
 

95GTV8

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Jul 25, 2005
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#7
  • Jan 16, 2006
  • #7
i didn't, do i need to disconnect the battery for 30 mins now? or since i've installed it and started it, am i past the point of no return?
 

95GTV8

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#8
  • Jan 16, 2006
  • #8
was thinking - could my new TB, have a TPS setting that is not very good? Would a bad tps voltage cause my hanging idle?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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Jan 16, 2006
#9
  • Jan 16, 2006
  • #9
95GTV8 said:
what exactly is the butterfly? I know of the base idle screw, what is the iac bleed control?
Click to expand...
I call the TB blade a butterfly (I am old school). Some TB blades have a hole in them, and this will raise the idle in and of itself.

Always check your TPS after installing a new TB or messing with the TPS. It should toss a code if it is unable to zero out the reading, but I dont hold my breath for that to happen.

A bad TPS can cause a hanging idle (TPS's dont fail that often though). Or you can find a hanging idle which returns to normal simply by shutting the car off and restarting it.

To clear the KAM, you can simply disconnect the battery and put your foot on the brake pedal for 5 seconds or so - this draw will discharge the capacitors in the KAM. That just saves some time.

Like Tim said, It is always good to clear the KAM after a new component is installed.

The idle can be controlled manually via the set screw (idle stop screw) and the IAC bleed. The bleed is on the front side of the IAC and has a rubber plug on it. Remove the plug and you will see an Allen-head screw in there. You can turn the screw to change the idle setting (loosen = higher idle/more air being bypassed. Tighten = lower idle, less air bypassing). If you loosen the screw too much, it will act like you have a vac leak and the idle will hang.

Good luck.
 

95GTV8

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Jul 25, 2005
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Washington State
Jan 16, 2006
#10
  • Jan 16, 2006
  • #10
allright thank you for all that info, i will go head out to my car with my flashlight and hopefully get this damn thing fixed, ty everybody for the help, and tim get on aim
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
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129
Jan 16, 2006
#11
  • Jan 16, 2006
  • #11
Hey man, I tried to reply to your PM and I cant send it because your PM box is full.
 

95GTV8

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Jul 25, 2005
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#12
  • Jan 16, 2006
  • #12
doh ok all cleared, that's probably why R.J. was online but i didn't get any messages from him. Stupid me. Ty for all the help hissin and everybody else.
 
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