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Old 09-30-2021   #11
Paul Workman
 
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Join Date: Nov 2007
Location: Squires (near Ava MO in the Mark Twain N'tl Forest) - Missouri
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Default Re: Random stall when coming to idle

I FEEL YOUR PAIN! Sounds familiar. Same thing here (1990 MY) as you described - especially on hot/humid days after fully warmed up AND at higher elevation(!!!!). A few things (including speaking w/ Marc!) seems to have fixed it (at least in IL):
  • Bumped the idle up (maybe 2-3 hundred rpm)
  • Re-calibrated my TB, to 5 IAC counts while set at .45VDC (big help!)
  • Installed (per Marc) the specific NTK O2s (see below) which are suppose to be more responsive.

And... I don't shift to neutral anymore when coasting to a stop: clutch only soas I can let the clutch out if it stalls in order to restart. Also, blipping the throttle right as I shove in the clutch to coast seems to all but alleviate stalling.

I don't know if the problem is isolated to the '90 cars, but stalling is a real PIA because even after I pop the clutch to restart it, when I do get stopped it has to sit still for 4-5 seconds before the idle drops from 2100 to normal - typical anytime the engine is first started on a '90, I'm told. And, if I don't have time to let it idle at a stop before having to go, I will have to do it at some later point or the idle speed will hang at 2100ish RPM while in gear or not. It must be completely stopped and allowed to reset before it will behave normally! (a PIA to be sure!) (Ami's '91 doesn't need to sit still for the idle to drop to normal, BTW.)
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Last edited by Paul Workman; 09-30-2021 at 09:59 AM.
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Old 09-30-2021   #12
-=Jeff=-
 
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Join Date: Jul 2007
Location: Bartlett, IL
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Default Re: Random stall when coming to idle

Quote:
Originally Posted by Paul Workman View Post
  • Bumped the idle up (maybe 2-3 hundred rpm)
  • Re-calibrated my TB, to 5 IAC counts while set at .45VDC (big help!)
  • Installed (per Marc) the specific NTK O2s (see below) which are suppose to be more responsive.
Based off your list:
I have not bumped the idle that much yet, but some and seems to have helped
I need to do a sanity check on the TB Minimum air setting
I also installed the NTK O2s after seeing drop outs in my Bosch O2s on the scanner
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