Engine BAP Sensor stop working out of the blue?


Founding Member
Nov 1, 2002
Baltimore, MARYLAND
Has anyone ever had a BAP sensor go bad, suddenly, while driving?

Doing new UPR front and rear suspension, and a rear rebuild, on a friend's healthy 347 powered 89 LX coupe. Did the rear suspension, and buttoned up the rear gears/bearings yesterday. Decided to go for a test drive, to make sure rear was quiet, and I usually make 2 or 3 laps out on the road in front of my shop. Didn't beat on the car, as it isn't mine.

Midway through, car popped twice, started stumbling, and dumping fuel, then stalled. Got it re-started, by holding pedal down to turn injectors off, but barely made it back to the parking lot out front, and then battery was quickly failing trying to re-start. I figured there was the issue...an alternator not charging, and battery voltage got low, so car wanted to die...but once inside, with charger hooked up, it still barely would run.

Clears up if I hold throttle up to over 3000 or so, but way, way rich AFR...

As it worked out, my test light has disappeared, as has my old EEC-IV code reader that I have had for 25 years or so, lol.

I'm going to do the test light, code pull, under the hood....I suspect the BAP sensor, but thought it was odd the way it happened, and was just curious if anyone else has had this type of quick failure.

The car is a new acquisition for him, so it's history is unknown for the most part.

And me....well, I've been MOSTLY out of the Mustang game for over 15 years now...so may be a little cobwebbed up, lol.


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