"SteveC" > wrote in message
...
>I have a 1990 C4 L98 with some engine issues. Any suggestions would
> be welcome. The problems seem to be temperature related. When the
> engine is cold, or the air temperature relatively cool, say below 75
> degrees, the engine generally runs fine. On hotter days, or after
> the
> engine has run for a while to get nice and hot, the engine loses
> power
> and runs very rough. At idle, the engine RPM oscillates up and down
> by a few hundred RPM when hot. Also, if I let the engine idle in my
> driveway for 15 minutes or so, it starts to over heat. That could
> just be a thermostat.
>
> I recently replaced the EGR valve, and I still sometimes get a code
> 32
> after a half hour of highway driving. The old EGR valve was clearly
> stuck open. Is there a sensor, like a temp sensor or O2 sensor that
> I
> should be looking for? Any ideas?

It's a bottom feeder and tends to vacuum up all sorts of trash, clean
it out of the front of the radiator.