Stang stalling, need help

[95Cobra302]

Wondering if you can help me. It's not my car, but my brothers 96 Mystic Cobra. When we are cruising along at like 45 mph or faster and we push on the brakes to slow the car down it just dies. It'll start right back up, and doesn't have any problems any other time. The car has been really well maintained and has only 50,000 miles. We are planning on changing the plugs and wires, even though they are only about 2 years old. I'm pretty stumped so if anyone has any ideas I will appreciate it.

 

[BlownFiveLiter]

You'll probably have better luck in 4.6 Tech, since this is their area of specialty.

Moved to 4.6 Tech.

 

[Bosko5.0]

When was the last time the fuel filter was changed.

 

[95Cobra302]

3 days ago

 

[trinity_gt]

Can you be a bit more specific? When you are braking, you mean to a stop? The engine falls below idle speed, sputters and struggles for a bit before stalling? Or is there a more serious failure of the engine acting like someone turned the key off while at 45MPH with the brakes on?

If it's the former (i.e. coming to a stop, the engine sputters and stalls), I'd suspect the IAC (idle air control) system. You may also want to check for a vacuum leak after the MAF; cracked ducting, loose throttle body connection, stuck PCV valve etc. If it's related to 45MPH (steady cruise), you may also have some EGR valve involvement; if the valve is sticking, it mimics a vacuum leak.

 

[95Cobra302]

Doesn't sputter or anything, just turns off like if you turn the key to the off position. Checked vacuum and got a reading of a steady 21-22HG.