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rough idle still..

  • Thread starter Thread starter roan65
  • Start date Start date Jun 10, 2006
R

roan65

Member
May 17, 2003
103
0
16
Wasilla Alaska
Jun 10, 2006
#1
  • Jun 10, 2006
  • #1
I'm still having issues getting this thing to run right. I have gone threw the sticky about the idle, everything seems good so far. no codes, cleaned the iac, checked vac lines, new sensors, relays ect...

At times it idles great, other times it idles so rough it just dies. I really can't drive it much because it keeps dieing at stop signs and such.

I set the idle with the iac unplugged to about 600, plug it in and it jumps to probably 1500. I'm stummped! I'm wondering if it is something with timing. However the distributor, coil, cap, rotor, and plugs are all new.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
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129
Jun 10, 2006
#2
  • Jun 10, 2006
  • #2
I get the idea you did a resto-retrofit - if so post up specs (SD or MAF, etc) so we can help.

Good luck.
 
R

roan65

Member
May 17, 2003
103
0
16
Wasilla Alaska
Jun 10, 2006
#3
  • Jun 10, 2006
  • #3
yes, I put a maf 92 into my 65. EGR eliminator kit, Canister purge and thermaculator eliminated as well. Edlebrock performer intake, 70 mm TB, C&L MAf calibrated to my stock 19lbs injectors. Might have a mild cam hard to tell.
 

HISSIN50

"How long does it take to get help in here?
15 Year Member
Nov 29, 1999
31,179
33
129
Jun 10, 2006
#4
  • Jun 10, 2006
  • #4
If the motor is up to temp, the idle shouldnt jump up like that (in my experience) when you reconnect the IAC connector. It should be doing almost nothing at hot idle with no load (tiny or no duty cycle).

I still see an underlying issue because with the baseline idle set with the IAC disco'd, that should be as low as the idle can go (because there's no IAC input). That is, unless your stalling occurs when the motor's not completely hot (or cold)....??

Ohming out the ECT can be a wise move if you think it could be contributing. Otherwise, the high idling and at other times stalling still sounds like a vac leak. A stockish motor should pull almost 20" hg at idle..............

That's all I got at 2 something AM. Good luck and bump.
 
R

roan65

Member
May 17, 2003
103
0
16
Wasilla Alaska
Jun 10, 2006
#5
  • Jun 10, 2006
  • #5
Thanks hissin for the input. I'll check vac again. With all the emission stuff gone I really don't have much for vac lines.

It will stumble hot or cold.
 
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