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Computer Failing?

  • Thread starter Thread starter slow5.0gt
  • Start date Start date Oct 14, 2007

slow5.0gt

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Aug 12, 2006
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Oct 14, 2007
#1
  • Oct 14, 2007
  • #1
Strangest thing, upon startup of 90 5.0 the car is at a very low idle eventually just dies. I check tps/iac (both of them pretty new). I get the base idle corrected to around 700 rpm. Idles great no surging nothing like that.
Turn off car I make sure the TPS around .98 volts. Plug in spout and IAC,try starting it up and its back down to 400 rpm again.

I can step on the gas and it will rev up quickly no hestiation but idle is the problem too low before dying wasnt exactly surging I checked jrichers list and did what I could off the bat.
But what I think is weird is that it seems to lose the idle setting after getting it corrected once I turn it off and start it back up.
 

jrichker

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Oct 15, 2007
#2
  • Oct 15, 2007
  • #2
Did you get any codes?

Once the mechanical base idle is correctly set, the engine's idle speed should not drop below that point. The IAC can only add air to increase the idle speed. It cannot take away air to reduce the idle speed below the mechanical base idle.
 

slow5.0gt

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#3
  • Oct 15, 2007
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I did try and pull codes I got nothing but the smog and air stuff with KOEO but unable to pull codes with KOER. Just searchs and searchs and nothing, or the car dies before im able to get my foot on the gas to keep it up.
 

slow5.0gt

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Aug 12, 2006
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#4
  • Oct 15, 2007
  • #4
jrichker said:
Did you get any codes?

Once the mechanical base idle is correctly set, the engine's idle speed should not drop below that point. The IAC can only add air to increase the idle speed. It cannot take away air to reduce the idle speed below the mechanical base idle.
Click to expand...

Thats whats weird why does the idle change after me setting the base idle and everything? Cant figure out why it does that
 
M

Mike85000

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Feb 22, 2007
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#5
  • Oct 15, 2007
  • #5
I would suspect that possibly your smog codes could play a role if your EGR valve is stuck open or something of that nature. If you are getting too much exhaust gas at an idle the mixture may be so screwed that it chokes out the motor.

Just a thought...
 
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