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A problem after nitrous kit install

  • Thread starter Thread starter kuwait
  • Start date Start date Apr 26, 2009

kuwait

Member
Mar 31, 2005
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Apr 26, 2009
#1
  • Apr 26, 2009
  • #1
i have a problem after installing the kit , car seem to idle around 2k Rpm and doesn't shift from 1-2-3-4 i have to do it manually and when i gas it , it would up shift at 4k to the next gear , any idea what might be causing that?
 

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
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Apr 26, 2009
#2
  • Apr 26, 2009
  • #2
What type of nitrous kit is it first of all?
 

kuwait

Member
Mar 31, 2005
194
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Apr 26, 2009
#3
  • Apr 26, 2009
  • #3
the noszle nitrous kit , its a direct port kit .

NOSzle Direct Port E.F.I. Nitrous System
 

tannerc91gt

This last 25% is foreign territory at this point
Founding Member
Nov 29, 1999
4,392
2,967
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Apr 26, 2009
#4
  • Apr 26, 2009
  • #4
Stock fuel system? That's a fairly expensive kit btw. Nice though
 

kuwait

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Mar 31, 2005
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Apr 26, 2009
#5
  • Apr 26, 2009
  • #5
yes its a stock fuel system.
 

trinity_gt

10 Year Member
Jan 31, 2003
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Apr 26, 2009
#6
  • Apr 26, 2009
  • #6
How much of what you did involved the throttle position sensor and/or its wiring?
 

kuwait

Member
Mar 31, 2005
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Apr 26, 2009
#7
  • Apr 26, 2009
  • #7
well it has a wot switch so i guess the Wot switch is wired to it.
 

trinity_gt

10 Year Member
Jan 31, 2003
3,125
81
99
Canada
Apr 26, 2009
#8
  • Apr 26, 2009
  • #8
If you did any wiring modifications to the TPS I'd suggest putting a scan tool on it that can display TPS volts and TPS percent and/or use a voltmeter to measure the TPS signal output.

I suspect that the PCM isn't getting the correct TPS signal anymore. If the TPS signal showed near WOT, the PCM might operate with an acceleration strategy, causing the delayed upshifts and causing the idle loop to stay inactive since it doesn't think the throttle is closing. Just a guess.

If the sensor is stuck at WOT (not just near), I'd expect you to have issues starting it as the PCM enters a clear-flood mode and turns off the injectors while cranking with the TPS wide open.

Measure the voltage and let us know what you find.
 

kuwait

Member
Mar 31, 2005
194
0
17
Apr 26, 2009
#9
  • Apr 26, 2009
  • #9
well here is an update , i decided to go through all the wiring and start with the TPS , it seems the shop did mismatch the wires , and indeed i had problems starting it without giving it hell to start , i just cut and rewire the tps to wot switch and it seems to have the car better , one wire is missing up so ill have to get a new connector , but no more idle problem and the car upshift as if normal , no down shifts tho.

thanks for the help guys , any more insight is welcome.
 
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