Engine cutoff

Hey there! I drive a 2003 Mazda MPV with 78,000 miles. Lately it has decided to shut off the engine at totally random intervals. It has NO objections to shutting off going 60mph on the highway, I however, have serious objections. Does anyone else out there have any experience with this issue? We have taken it to our very trusted mechanic and left it for 3 days to have them say the OBD does not show any problems and they cannot get the van to turn off in their possession. OF COURSE!! Someone help me please.

I would assume this is due to an electrical problem. I would first check the ignition switch area and then the ignition system power. Tapping on suspected trouble areas may help find the problem.

It’s near impossible to say given the fact we do not know if the problem is fuel or spark related. Being able to narrow it down helps tremendously.

Here’s a suggestion and some wild guesses.
Drop by a local AutoZone, Checkers, Advance, etc. and have them scan the vehicle. Sometimes an outside opinion can be beneficial. They will perform this service for you free and post any results back here for discussion. Do NOT expect the parts house to diagnose the problem; they only scan the vehicle and give you the results.

If the vehicle sputters before it quits it could possibly be related to the fuel pump failing. The mileage is a bit low for a pump failure but if the fuel filter has never been changed it’s possible.
If the vehicle just flat shuts off without a whimper then I’d be leaning towards something failing in the secondary ignition (control module, etc.) or possibly the ignition switch.

After the vehicle quits do you have to sit and wait a while before it restarts or does it generally restart instantly or within a minute or two?

Thanks for the response!

No sputtering, but the filter has not been changed. There is no whimper, scream, or shutter. It just quietly and almost undetectably shuts down. Were it not for the lack of power steering and the indicator lights all lit I could easily just glide down the road.

It does start right back up once put in neutral or park.

We are going to try replacing the fuel filter, plugs & wires, air filter. Hopefully there will be some narrowing of the array.

It’s also possible that this is being caused by a faulty security system or inertial cutoff switch.

Ther are lots of possibilities here.