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The IACV is an automatically controlled valve that lets a precise amount of air in to maintain idle speed, WHEN THE THROTTLE PLATE IS CLOSED (i.e., foot is off the gas).

When your foot is on the gas, even a little, as you mention you have been doing following other good advice above, the IACV is basically bypassed. The engine will get any air it needs through the part-open throttle, and the IACV may add air on top of this (making for surging, or other weird things if the IACV malfunctions) but should not be preventing your car from starting.

IACV cleaning is definitely something that is commonly needed on these cars, and anything you do there will probably be helpful (just as replacing the main relay was), but I would not expect it to solve this problem. There should be plenty of other threads with details on the cleaning on this site.

Briefly, at least on my '99, I needed to remove the throttle body to get the IACV off, and was able to clean it using q-tips, brake cleaner, and patience, without opening it up ... until the last time I cleaned it when this would no longer get it sufficiently clean. That last time, not having the 5-pointed screwdriver needed for those screws, I used a Dremel tool to cut slots in the tops and used a slotted screwdriver. BTW, in removing the throttle body, you'll find instructions that say the paper gasket has to be replaced. The first time I did that, it was true - the paper was bonded and ripped and needed replacement. Since then (twice, I think), the gasket has not needed replacement, but I keep a spare on hand just in case.

So I don't want to slow you down on the IACV. Do it. Do it well. Have fun at it. It will be good for your car. But don't be disappointed if it does not really solve your problem today.
 

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Discussion Starter #22
Thanks odskewel. I like a good problem. This is not my primary car so I have plenty of time to figure it out.
I'll do the IACV another time.
Something will eventually present itself and lead me to the solution.
I'll post back if I find something.
 

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Discussion Starter #23
Hi Guys. I'm just giving this thread some closure.
It ended up being a blown head gasket.
There was coolant in the cylinders.
Once it started . . . it ran great.
But getting it started was the issue.

Thanks again for all your patience and support.
Joe
 

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Oh man, tough break!

Some heavy wrenching ahead...

Dave
 

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Thanks for this thread! I was able to locate and repair my main relay today in about 20 minutes. Found a broken solder joint for the fuel pump
153946
 
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