high rpm's when braking

[02ponyboy]

im having an intermitten problem with high rpm's. on occasion when im in a position to hit the brakes hard the motor will rev to @3000 rpm's. could this be a vaccum problem? iac problem? or can it be something else? im pretty sure it does this when im pushing in the clutch to downshift. any help guys??

 

[Torinalth]

yeah, your shoes are too big.... not joking either. i love my doc martins but i had th same issue.... i brake hard, and this pushes the brake passed where the idle position of the gas pedal is... thus my shoe biing so wide it pressed the gas as well... made a bunch of people scared when my RPMs spike to 4k wheni am ripping the brakes because i misjudged my stopping distance or got caught on a red light. since i got slimmer shoes i no longer have the issue unless i panic and miss my exact placement on the brake. seriously... take your shoe off and put it on the brake with you on the floorboard, see how wide it is compared to the brake pedal.... took me no time to figure it out, however i freaked and tore my upper engine apart trying to find an issue, when it happened a second time my shoe caught the SIDE of the gas pedal with the side of my shoe (ribbed sides on the docs) and then it immediatly clicked.

check this first before you start spending money. i know it sounds silly.... but it happend to me. so now i only wear my docs when i drive an automatic. kinda sadens me too, i love my docs.

Torinalth

 

[02ponyboy]

i guess i hadn't really thought of that, but that would have probably happened to me in 1 of the 5 other mustangs ive had in the past. i guess this problem has stumped everyone like it did me! thx for the theory though.

 

[myponyrocks]

actually, check under your hood, at the front drivers side there should be a sticker from Ford with the latest software update they put on it. Mine had that problem after Ford upgraded the tune.

Since I got my predator it no longer does that. Also your IAC could be at fualt.