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Sound Vacuum Related?

  • Thread starter Thread starter 91foxbod50
  • Start date Start date Sep 20, 2011
9

91foxbod50

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#1
  • Sep 20, 2011
  • #1
I have a 91 GT that i recently got running. Problems im having seem to be Vacuum related. Mainly because of the upper intake. Its a gt40 intake that was on the car. It has tons of vacuum lines 3 large vacuum lines out of the rear of the intake and 1 small with 2 large out of the front. The front also has one vacuum line that bends in an upwards angle and comes out past the front of the intake.

The problem im having is at idle when giving gas itll bog and then clear up. So its missing a little. I adjusted the TPS and set the timing. (Which was off) Im most likely going to adjust the TPS again because last time when i set it the timing was bad.

But any other ideas? All of the smog Acc are off EGR is capped as well.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#2
  • Sep 20, 2011
  • #2
No way to troubleshoot vac lines over the interwbz but are you sure that your TPS is even any good?

You should not have to,"SET" your TPS at all. When you turn the ignition switch on, the EEC will take a reference reading then scale itself to the TPS accordingly.

If however, the TPS is inconsistent (read: bad), then no amount of fiddling with it will make any difference.
 
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91foxbod50

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#3
  • Sep 20, 2011
  • #3
well in this case the throttle body is stock and the itake is a gt40. so it would need some adjustments wouldnt it? before i had ajusted it, the car wouldnt even run. So hopefully its good if it has gotten me this far.
 

Noobz347

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#4
  • Sep 20, 2011
  • #4
So what TPS adjustment do you intend to make on a stock TB?
 
9

91foxbod50

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#5
  • Sep 20, 2011
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Adjusting it so it would run.. it wouldnt run under load. give it the gas and itd bog out and stall. After making adjustments it ran fine.
 

Noobz347

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#6
  • Sep 20, 2011
  • #6
Are you hogging out the holes and rotating the TPS?
 
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91foxbod50

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#7
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yea. is there an easier way? lol
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#8
  • Sep 20, 2011
  • #8
Yeah... don't modify the TPS at all. If they were intended to be, "adjusted" they would have come that way.

Install your TPS in the factory position. Disconnect your battery and hold your brake pedal down for 30 seconds.

Restart the car.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#9
  • Sep 20, 2011
  • #9
Please read the following:

http://www.stangnet.com/mustang-forums/825424-adjusting-your-tps-0-98v-not-necessary.html
 

7991LXnSHO

wanna catch the space herp
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Sep 21, 2011
#10
  • Sep 21, 2011
  • #10
With a cam, I had to open the idle screw a little, and then adjust the TPS to get it below 1.1 volts. Then it runs fine. I had to file the holes a bit. Stock place would not do it.
 
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