Stubborn 93 Saturn SC2 with stalling, 32, 45 diag codes

Wonder if anyone else has ideas here, I'm about stumped!

I've got a 93 SC2, manual transmission, with 153,000 miles. It idles
high (1300 RPM), but a check with carb cleaner spray didn't find any
vacuum leaks.

The real problem is this. After the car is warmed up (10 minutes
driving), I'll idle at a stoplight for a minute, then when I step on
the gas, the engine sputters, the tach shows the RPM dropping, and the
car stalls. Usually, if I just step on the gas lightly, the tach will
drop a few hundred RPM for a second or two until something becomes
"unstuck" and the the RPM rises above 1300. The worst was on a wet
day, when it would stall unless the car was in gear. The error codes
I get are 24 (VSS fault. = It stalled, duh!), 32 (EGR System Fault),
45 (Oxygen Sensor).

My first thought was "incorrect fuel/air mixture".

So far I've done (in order):
- Remove Throttle body, clean out with carb cleaner, replace Throttle
Position Sensor (TPS) and Idle Air Control (IAC), reinstall Throttle
Body with new gasket
- Replace Oxygen Sensor
- Replace EGR Valve (and gasket) and EGR Solenoid

Each time I've reset the error codes in case the PCM works differently
with codes stored.

The car still does the same thing, though possibly not quite as often
(hard to say). My Chiltons and Hayes books are about out of ideas as
well. At this point the PCM is the only other thing I can think of.

Let me know your thoughts.

Thanks,

 

Has the coolant temperature sensor been replaced?

The CTS that feeds the computer is prone to failure and can cause such
symptoms. - k.

 

The real problem is this. After the car is warmed up (10 minutes

My bet for at least part of the problem is the VSS. It didn't throw the code
because "It stalled, duh!" it threw the code because there is a problem with
the Vehicle Speed Sensor. If you haven't noticed, the car idles higher(like
around 1300) when the car is moving, like, coasting in neutral or with the
clutch in. Since it is idling high just like it does when moving, the computer
probably thinks the car *is* moving due to getting faulty information from the
VSS. And, since you have a code telling you there is a fault with the VSS, I'm
betting your problem(or at least part of it) lies there.