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Code 29 - Anything Limping?

  • Thread starter Thread starter Reed
  • Start date Start date Sep 11, 2006
R

Reed

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Mar 31, 2005
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BC, Canada
Sep 11, 2006
#1
  • Sep 11, 2006
  • #1
Finally got the car feeling better. Pulled the codes, got a 29 on the memory scan - no reading from the VSS. I am pretty sure this is because I screwed up my speedo gear install and I have a new one waiting to go in. What I want to know is what problems does a non functioning VSS cause?

I am going to the track in a couple weeks and would like everything to be working properly. Would the VSS not working put anything in limp mode? Thanks!
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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Sep 11, 2006
#2
  • Sep 11, 2006
  • #2
You wouldnt have idle compensation while rolling - that's the biggie that comes to mind.

Good luck.
 
R

Reed

New Member
Mar 31, 2005
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BC, Canada
Sep 12, 2006
#3
  • Sep 12, 2006
  • #3
Thanks for the reply, I'm still learning a lot about these cars. What is idle compensation and why might it be important while the car is running/rolling?
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
34
129
Sep 12, 2006
#4
  • Sep 12, 2006
  • #4
Reed said:
Thanks for the reply, I'm still learning a lot about these cars. What is idle compensation and why might it be important while the car is running/rolling?
Click to expand...
Let's say you're coming off the highway and are coasting in neutral at idle, down the off-ramp. You hit the brakes, use power steering to change lanes, etc. All this can add up enough to bog the engine down a little. The VSS and IAC work hand-in-hand to keep the revs up while you are in neutral (and off the gas). The VSS is what notes that the car is rolling (I call it a rolling idle). And the puter will keep the rolling idle at 1100-1500 RPM (depending upon year, mods, base idle setting, etc). It keeps the car from stalling.

If you have your idle set on the higher side, you might not notice any issue (there are stangers who dont run a VSS and set the idle to accomodate a little extra bogging/accessory load). Remember, the stock idle is ~652 RPM, and that doesnt leave much room for it to go lower.

Good luck.
 
R

Reed

New Member
Mar 31, 2005
78
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0
BC, Canada
Sep 12, 2006
#5
  • Sep 12, 2006
  • #5
HISSIN I apprecaite the responses. I guess I can be lazy on the VSS a little longer. Thank you for the replies!
 
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