The problem started awhile back, and was diagnosed by Mazda as a tensioner pulley. Two were replaced since November 07, one chewed up the serpentine belt. Mazda suspected a problem with their supplier. Now however, the problem starts with a slight chirping that seems to be in synch with engine revolutions, but will finally result in a LOUD squall with the truck shutting down completely. This can even happen at speeds of 50+ mph. The truck always starts right back up repeatably, but this is getting more frequent and the dealer has not successfully diagnosed the fault. We have put a stethoscope on all of the ancillary items and each pully is smooth as silk. Of course, it wont HOLLER and stall when we are under the hood trying to replicate...

Questions:
1. I can't imagine anything that connects to the serpentine belt stopping the truck dead, can any of you?
2. Can the distributor be binding? Where is it located? I see the square cap with the plug wires on the right valve cover, is there a spinning distributor beneath that? The slight chirping sounds like it is coming from back there somewhere.
3.Any ideas on what could be related to loud SQUEAL and cut out? Electrical? Mechanical? Electro-mechanical? If so, what?
4. Could it be something like the crank position sensor faulting and causing a timing slip/squeal just before shutdown? Anyone heard of this?
5. One more unrelated question: The upper radiator hose is collapsing on cooldown. Is this air in the system, or is there a blockage in the resevoir tank?

The truck runs perfectly, with smooth idle at all times. Is there an on-line service manual that is downloadable out here?

I appreciate any help offered greatly, and I promise to publish the final fix, once found, to help others. All suggestions are welcomed.

Thank you and best regards,
Charlie
Fairview, Tx

 

1, 3. Is your AC compressor locking up, seizing intermittently? How about a different accessory or tensioner? Yes, these things could cause a stall; a traditional non-toothed belt could slip and burn in that situation but a toothed serpentine belt will stall it. Could you purchase a belt for your model that doesn't have AC and install that for a week to see if it goes away (of course, you wouldn't have AC).
5. No, that's not due to air in the system, a collapsed hose is due to vacuum. A vacuum should suck coolant back in from the reservoir, and the hose should uncollapse. And maybe a new, good-quality hose needs to be installed there.