Engine dies when braking hard

[Ozark]

I recently rebuilt the rear brakes on my '86 Carrera and while bedding them in per PMB's advice I encountered a problem. Twice when braking hard from 80mph to 10mph, the engine suddenly died and then restarted after downshifting to second gear and releasing the clutch, like it was roll starting. Every other time (8X60-10mph, 4x80-10mph) the engine ran normally. Any ideas why the engine died in only those two instances?

TIA,
Gordon Watkins

[PeteKz]

Is the fuel level in your tank low? The pump could have sucked some air.

[Otter74]

I’m not entirely clear on what you were doing - were you in gear the whole time, or did you put it in neutral?

[rwest]

Just spitting this out, but any chance you have a vacuum leak in your braking servo system and the hard braking allowed unmetered air into your engine causing a lean condition?

[2.7RS]

Did you press the clutch when pressing brake pedal at the same time?

2 foot in if you know what I mean???

[Math]

Originally Posted by rwest

Just spitting this out, but any chance you have a vacuum leak in your braking servo system and the hard braking allowed unmetered air into your engine causing a lean condition?

I been trying to figure why my brakes don't work well after my engine rebuilt, vacuum leaks came to my mind right away...

[Ozark]

Originally Posted by PeteKz

Is the fuel level in your tank low? The pump could have sucked some air.

I had 3/4 of a tank.

Originally Posted by Otter74

I’m not entirely clear on what you were doing - were you in gear the whole time, or did you put it in neutral?

In 5th gear then hard brake from 80mph to 10mph with clutch in. I did this several times in a row. It didn't die every time but twice it did and then re-startted when the clutch was released after shifting to 2nd gear. This is the break-in procedure for new pads recommended by PMB Performance, where I purchased the pads.

Originally Posted by 2.7RS

Did you press the clutch when pressing brake pedal at the same time?

2 foot in if you know what I mean???

Yes, when I reached 80mph, hard brake with the clutch in. Engine died then re-started when I shifted to 2nd and release clutch pedal.

Thanks for the responses.

Gordon

[wswilburn]

My guess (uneducated as usual) is a vacuum leak at the brake booster.