1997 civic stalls at idle once hot

My '97 civic dx hatchback started stalling while idling once it gets hot. The car starts fine and runs ok, but once the engine gets hot, around 15-20 mins driving time, it will stall once I come to a stop.
It will crank back up and run fine until the accelerator is depressed, then instead of returning to an idle speed it should, it dips way below that and stalls. I have not found any vacuum leaks and no codes are generated by the ecu. Any ideas? It's a 5sp manual, it that matters, with 296,000 miles.
Thanks, Tom
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snipped-for-privacy@nortelnetworks.com wrote:

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Wow . . That's one of the best-written descriptions I've ever seen.
Anyway, how full is the reservoir? Is the temp needle going higher than previous? With a flashlight, have you checked how full the coolant reservoir is at the end of the day, and in the morning?
I think you're low on coolant and / or your rad fan isn't cutting in because of it.
Not related much, but have you replaced the PCV with a Honda one?
'Curly'
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I'm almost certain my coolant level maybe low. I will check that this evening. I've never replaced the pcv valve. Think I actually bought one once, but could not find it so who knows where it ended up.
Thanks, Tom
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btw, the fuel and air filters are both new enough to not need replacement yet
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Hi 'Curly'
The resevoir tank was empty and the radiator took a bit of fluid as well. I think filling both made some difference (or was that due to the outside temps dropping 30F?), but the car still cuts off at idle. I have never replaced the pcv valve. What do you guys suggest next?
Thanks, Tom
'Curly Q. Links' wrote:

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tom misiak wrote:

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Check the reservoir and top up to MAX if it's gone down overnight. As the engine 'burps' out air, it will sip the reservoir dry each time you cool the engine down. Use Honda premix, and no tap water.
'Curly'
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These are the classic symptoms of a failing distributor coil: As they begin to fail, they get finicky after warmup. How old is the car's coil?
My 91 Civic coil did the exact same thing a few years ago: After 20 minutes or so of warmup, the car would die at stops. Eventually it would have to be allowed to completely cool down before it would start again. It got worse and worse.
But try checking the coolant levels, like Curly said, first. I'm not optimistic that it's a coolant-failing-to-get-to-engine-control-components problem, but it costs nothing to do this.
Are your ignition wires, plugs, distributor cap, and rotor up to date?
Fuel filter and air filter?

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The plug wires have been replaced within about 20,000 miles with Honda ones due to some other ignition type problems I had at that time. The plugs are NGK and have less than 20,000 miles on them and look ok. The dist cap and rotor are both up to date, but from AutoZone or Advance. Distributor coil, eh? Any way to check it, or just replace? What are the odds that this is caused by IAC? Btw, if I turn the a/c on the car never stalls albeit guess that's expected since the ecu increases idle speed?
Thanks, Tom
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If it's the IAC, then from my reading the most likely culprit is inadequate coolant to it.
There are some resistance tests one can do on the ignition coil, but even if the coil passes them, word here is that doesn't mean it's working okay. The tests should be given at the following online Honda manual, under I believe electrical, ignition system: http://www.honda.co.uk/owner/CivicManual/index.html
I would consider going with OEM on the cap and rotor. It's only a few more bucks. I have gone non-OEM on parts like this in the past and found it to be a mistake, generally speaking.
I'd be guessing with the A/C but wouldn't use that datum to rule out any of the above.
The distributor and its parts are the Achilles' heel of 1990s or so Hondas.
Elle -- Honda home studies: http://home.earthlink.net/~honda.lioness /

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