intermitent stalling

[Driver]

hi im working on a 93 sho right now i just fixe the steering wheel shudder by turning the rotors
and now im moving on to an intermitent stalling problem
the engine speed will drop to 500Rpm and rise back to idle for about 20-40 seconds and then will stall then you start it back up right away and sometimes it does it sometimes it doesnt
if you leave it in gear (automatic) then it usually stalls but if it is in nuetral then the car does not always stall
i read somewhere it might be the cps it might be the maf sensor it might be the vehichle speed sensor i dont like throwing parts at things i am also getting trouble code number 176 which states that oxygen sensor bank two is running lean
are these two things tied in? possibly the maf sensor is giving false readings?
any help would be greatly apreciated

 

[jthomas68]

To check the MAF,just unplug it.You wil get a code,but it would run fine.If it still runs bad,the MAF is fine.

 

[SHOemup]

If you have had a recent or now have a coolant leak coming from the waterpump, then chances are it would be the CPS. That is the only time i've heard of the CPS going. Coolant leaks onto it causing the car to shut off and then leaks onto the cats and burns off leaving no sign of a leak. Other than that, i've never heard of the CPS going.
Good luck

 

[stevetatro]

I don't necessarily correlate a bad CPS to a leaking/failing water pump.

I've had to replace my waterpump twice because they've totally crapped out (and leaked all over the place) but I've never had to replace my CPS (furiously knocking on wood).

On the other hand, I've heard several members that have never had a waterpump leak that have had to replace the CPS.

Not saying the two aren't related, but they don't always go hand-in-hand.

 

[stevetatro]

Oh, and these kind of idle problems are often due to a failed IAB valve.

 

[TwiceSHOwn]

I assume you have re-learned idle...try that first. Clear the computer then make sure all the accessories are on and let the car learn idle again. Then trouble shoot.

When my car did this it was the MAF.