A brake booster works off engine vaccum to "assist" or "boost" the braking power. If the vacuum system leaks, it can/will let a LOT of unmetered air into the engine, causing a stall.redneck5150 said:i got 1991 samurai has 1.3 with fuel injection. just started doing this today when ever i step on the brakes the engine dies. it will idle high when first start it then it idles iraticaly till it warms up then it idles fine with the ebrake on but if i step on the brake pedel the engine dies and wont start till i let of the brake pedel. did a search and came up with nothing any info would help thanks.
Remove the vacuum boost line on the intake manifold (follow it from the brake booster) and plug it with a rubber cap. If you can brake without the engine stalling, you've got an air leak somewhere in the power brake system.
WARNING, you will NOT have power brakes, take it easy, do this in a parking lot or somewhere SAFE.