Zackman, lets try to look at this with some logic instead of just saying it maybe this or that. We know the Ac compressor puts a really heavy load on the engine right? So the heavy load makes the engine stall out. But obviously its not supposed to stall out, otherwise there would be alot of stalled Sentras when its hot. The FICD valve or the Fast idle Control Device is a little solenoid that the ECU engages and allows more air to get to the engine to compensate for the heavy load from the AC compressor. If this ain't working, your motor will likely die. If your Sentras has a higher mileage, the little port the air is allowed to pass through can be clogged up and it will be the same as if you didn't even have the FICD. Thats probably my first suspect. With the heavy load of the AC compressor and the engine idling, for the engine to maintain a steady idle it needs more air. When the throttlebody is clean, there is a small clearance that allows abit of air to pass to allow the engine to idle. This is with little or no load. Then there is another valve that opens or closes and keeps the idle in a certain predetermined range. This can compensate for a light load, like the defogger, headlights etc etc. The FICD valve is there for the heavy loads like the AC compressor to give it just enough more air to keep the motor to tick over steadily. So at idle with the AC on, you need the wee bit of air from the throttlebody + air passed from the idle management valve + the air the FICD valve allows to keep the idle up for the motor to idle. Lose any one of those and the motor will die when you turn the AC on. A dirty throttlebody might choke off just enough air that the FICD can't compensate so I'd clean that with some carb cleaner while you are at it. You can do a quick check with the FICD valve by giving it 12V, it will go CLICK CLICK as it opens when the power is applied. Just make sure you use an inline fuse if you plan on testing with the car battery. Careful when you take the FICD valve off, it has lil' spring loaded bits that like to fly everywhere and play hide'n go seek. Ken +----------------------------------------------------------------------+ To unsubscribe, put "unsubscribe" (by itself) in the subject and send to [EMAIL PROTECTED] or use the form at http://www.sentra.net/sml
