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Surging Idle

  • Thread starter Thread starter slow5.0gt
  • Start date Start date Aug 16, 2006

slow5.0gt

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Aug 12, 2006
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Aug 16, 2006
#1
  • Aug 16, 2006
  • #1
Does anyone else have a surging idle upon a cold startup but after 10 mins or so it goes away and idles just fine? I looked in the surging idle checklist but still wasnt clear on what causes that.
It just reminds me of my friends integra that did that on cold days to warm up faster.
 
D

dude5l

Founding Member
Dec 24, 2001
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Grande Prairie, Alberta , Canada
Aug 16, 2006
#2
  • Aug 16, 2006
  • #2
Mine does the exact same thing. Once it gets up to temp it seems fine. Iblame it on not having a chip burnt for it yet. What mods do you have?
 

jrichker

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Aug 16, 2006
#3
  • Aug 16, 2006
  • #3
Go through the surging idle checklist and fix the things you know need fixing. That includes dumping the codes, fixing the code items and replacing old vaccum lines. At that point, plan on replacing the IAC if you still have a cold start idle problem that didn't clear when you did the neeeded maintenance.
 

slow5.0gt

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Aug 12, 2006
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Aug 16, 2006
#4
  • Aug 16, 2006
  • #4
full boltons,gears,cam ported heads
 

795.0pacecar

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Aug 16, 2006
#5
  • Aug 16, 2006
  • #5
Mine does that too, and it always surges when the a/c is on. I blame speed density.
 

HISSIN50

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Nov 29, 1999
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Aug 16, 2006
#6
  • Aug 16, 2006
  • #6
79PC, Have you yanked codes lately? On my '88, the only time I got surging was when the IAC decided to go on walkabout and idle-up too high. I was spittin an upper-limit code and it surged with AC on (only).
Just an idea (that I'm sure you checked already).
 

slow5.0gt

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Aug 17, 2006
#7
  • Aug 17, 2006
  • #7
A curious thing I found out was that if I raise the fuel pressure the surge lessens/ stops when I lower it the surge comes back.
 

795.0pacecar

lover of pudgy polygamists
Jul 11, 2003
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Senoia, GA
Aug 17, 2006
#8
  • Aug 17, 2006
  • #8
HISSIN50 said:
79PC, Have you yanked codes lately? On my '88, the only time I got surging was when the IAC decided to go on walkabout and idle-up too high. I was spittin an upper-limit code and it surged with AC on (only).
Just an idea (that I'm sure you checked already).
Click to expand...

It doesn't thown any codes that matter, all the codes are thermactor codes. Im on my 3rd IAC and 2nd TPS and every other sensor is new. Im converting to mass air in a week, so well see if that helps. My problem could also be that the computer doesn't know when the a/c is on. On the 86+ the HVAC controls connect to the computer, and run through to the pump, on mine that is all bypassed so the HVAC controlls run straight to the compressor.

If I knew which wire to tap into the a/c system from the computer I would.
 

Supaman

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Hawaii
Aug 18, 2006
#9
  • Aug 18, 2006
  • #9
Check your distributor. If the armature gets in contact with the stator, it could be causing your trouble.
 
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