88 80Q won't start or idle when cold unless you crack the throttle

Ado Sigal a.sigal at bluewin.ch
Sat Oct 14 18:10:42 EDT 2006

Sound like the ISV is not operating, probably stuck. Disconnect the exit 
side of the ISV and see if the revs would rise. If yes, the ISV is the 
reason. Since it idles fine when hot, one can assume that wiring and 
contacts are ok, take it out the ISV, hot-wire it and spray in and out 
with carb cleaner, and if no buzz, keep hitting it with something that 
would do no damage, as to shock it, and continue until it starts 
buzzing. Finish the cleaning while in operation. BTW, WD40 also works well.



MXHOWES at aol.com wrote:

>I posted this question a few months ago and only got one reply suggesting a  
>stuck air meter plate which wasn't the problem any other suggestions?
>My 88 80Q was parked in the garage for 6 months undergoing a  heater core 
>transplant. I just got it running again but I picked up a  strange startup 
>problem. The car will not start when cold unless you press  down on the gas just the 
>smallest amount. If you crack the throttle, it will  start right up, if you 
>take your foot off it tries to idle at about 400  RPM.  When cold you can make 
>it idle ok ~900 RPM by applying a little gas  by foot, the mixture is correct 
>because no mater how cold it is it idles  smoothly (with your foot on the 
>gas). After a few minutes (or miles) you can  remove your foot and it will idle as 
>normal. When hot, just  hit the key  and it starts up right away.  The heater 
>core replacement requires a  complete dash removal and lots  of wires were 
>disconnected. I didn't have  to touch any wiring under the  hood.
>The car started perfectly when cold  before the heater core operation and 
>still runs great, it's just that something  isn't right.   Any ideas?
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