1993 Mazda 626 The engine sputters, shuts down..

Hi davesac11789,

Thank you for the donation.

If each time the engine stalled due to charging problem, then you have a problem that is quite common but does not have any remedy.

Seems the alternator does not charge intermittently causing the problem

Some have changed the alternator a few times but problem recurred after some time.

Does the charge indicator light shows prior to the engine stalling?

Thanks for your response. No, the charge indicator light did not come on, but the brake light came on shortly and then shut off shortly before the car died. I didn't think much of it at the time, but maybe that can help you with your diagnosis.

Other info: The IAC Valve has been in need of replacing over the last few years, just an expensive change for something uneccesary (I've just been dealing with the high idling issue when its in park: 2000-2500 rpm "up, down, up, down.." and when its in drive: a consistent 1500 rpms) This may have something to do with it as well?

Any help is very useful, I appreciate it

The brake indicator lights showing could indicates a likely fault with the electrical system and it should be the result rather than the cause of the problem.

If the idling is surging, it might not be a faulty IAC but rather a leaking vacumn or the idling speed is adjusted too high.

Clogged coolant hoses of the IAC wouls also cause surging.

For the non charging, there are 3 possible reasons and you might have to install a voltmeter to monitor the charging.

1. Faulty alternator

2. Faulty PCM

3. Faulty ignition switch, but this is not likely if the radio etc does not stop working.