Engine stumles when braking

95 explorer 4.0l ohv. I go to take off and then come to a stop after about 10-15 feet, i just give it a little gas then lightly press the brake, rpm's drop to around 400-500 then back to normal. I have replaced:
IAC
MAF
Plugs & wires
Coil pack
intake manifold gaskets
fuel system cleaner
fuel filter
air filter

Please help.

Does the engine run smoothly, both at idle and under load? Did any of the parts you replaced make any improvement in the issue? Have you checked for vacuum leaks (the power brake booster uses vacuum to provide the power assist)? Have you checked the charging system voltage when you step on the brake pedal? Have you opened the throttle plate and checked for build-up? What type of spark plugs did you install?

-Rod

Try a smoke test on the brake booster + Intake system.

Do a Google ''Youtube diy auto cigar scotty''

engine runs real smooth at both idle and under load, all the parts that i listed have been replaced within the year, the truck would start acting up, and i check my haynes manual, do the test from the book, if they weren't within the parameter i would then take them to my local parts store and then have them run the same test. if it was indeed bad i would replace it. I have had some bad luck with this truck lately. and everything i have replaced it needed, because before it wouldn't run or it would even start. i have looked for vaccum leaks i can't seem to find any, i've tried the hose to one ear and move it around to various places. i have a built in voltmeter in the dash and it doesn't move once the vehicle is on, if you know a good way to test it please inform me. i have recently had the whole intake system apart and have cleaned it all, from air filter to intake ports on the cylinder heads. i installed iridium plugs, but that was like a year ago and it hasn't had this problem the whole time. Thank you