:banghead: I have a 2000 SE with an SR20. It has over 125k miles and has treated me very well. But lately while Im driving, sometimes the revs fall at idle and the car dies. This also happens when when Im driving at high speeds and i shift into neutral....the revs drop down until the engine stalls. What could this be? The alternator? I took it to a shop and serviced the throttle body but it didnt help. Its scary to be driving 70mph and then the car stalls and I lose power steering.

maf sensor, or some other sensor, thats a pretty vague description. try checking your egr with a vacuum pump to see if it holds vacuum, clean your mafs carefully with some specific maf sensor cleaner, get ahold of an obdII scantool and check your oxygen sensors...there are a number of things i would look for but think, it mostly involves a sharp rpm drop to idle, then something cant maintain that idle. so you can rule out basic fuel/spark/timing/compression. most likely an engine sensor.

oh yeah and make sure they properly tensioned those new belts. too tight can cause excessive parasitic power loss(and the engine doesnt know it so it wont compensate when the rpm drops. try and find a belt tensioner guage, most garages and some mechanics have them. but if your not a mechanic its not really that realistic to buy one, as most tool companies charge like 200 bucks for it.

Sounds like a distributor. Remove distributor cap and check for oil. Either way the cranks sensor is part of the distributor and can make your car stall. I would look at the distributor first. gl..