OT: Car stalls at idle when hot, and then won't start

[Black]

Not vapor lock-- see grateful's accurate description.

Is anyone going to go search for fauch?

[fauch]

Sorry guys,

It is a 1995 Daewoo Super Racer with a 1.5L DOHC 16V engine, 5 speed manual transmission, with 150k miles on it (don't laugh that isn't a lot at ALL for cars in this country). But the engine "looks" brand new, doesn't leak or make noise at all etc so I assume it was swapped out or rebuilt at some point in its career...

EFI so no carburetor...

Strangely enough (or not) the check engine light does NOT come on.

And while it's been WARM here (70s), it is certainly not HOT, and it happened to me at night as well...

Oh another thing, there is NO smoke whatsoever from the exhaust when the car is running normally, but when the problems start it starts to smoke which worries me that there is a LOT bigger problem here than fuel injectors....

[fauch]

testcase wrote:
Have you tried giving it a good kick?

Yeah, and the bumper fell off :'( (just kidding)...

[Thrift Store Scott]

billb wrote:
fuel flow
MAF or any number of sensors, though they should show up in codes
EGR ?

not so sure a filter would cause a stall at idle as fuel flow should be low then but filters do weird things

It sounds like the EGR (Exhaust Gas Recirculation) valve is sticking in the open position. When working properly, EGR valves are shut at idle and open at all other times. When one sticks open it will cause the car to run rougher and rougher at idle until it stalls, especially at red lights and especially on hot days.

EGR valves are usually actuated by manifold vacuum run through a thermal vacuum switch that only opens once the engine has reached operating temperature, so the first thing to check would be the condition of the associated vacuum lines. If the vacuum lines are okay, then replace the valve itself... they're usually only held on by two bolts and aren't expensive, although clearance and access can be a problem on some cars.

[mrlynn]

What color is the smoke?

/Mr Lynn

[space-time]

fauch wrote:
I was "given" a replacement car at someone else's expense for one that was stolen from me (don't ask, it's a very convoluted story) ...

would probably be fun to read while waiting for data acquisition or teaching a student how to NOT blow up the plant