Vacuum Opens Throttle Plate - Voyager 94-mod 3.3L V6 4WD
 

Hello! This is a very strange and unusual problem, that i have been discussing with other mechanics, and they have no clue. I've also been troubleshooting alot, that i will elaborate further, so please read before trying to help me

Problem: When the car is put in Drive, it accellerates full throttle forward, without touching the pedal.


What happens: The vacuum from the engine sucks the throttle plate open. The ones i have been talking to, says it's not possible, but it is.

Cause: Unknown. This is what i need help with. What creates the vacuum?

"Something else is opening the throttle plate" - NO!. I've taken apart the whole throttle assembly, and i am 110% POSITIVE there is nothing else that can influence the throttle plate but the vacuum from the motor.

Note that everything was working perfectly earlier, until i removed the wire to the cruise control unit (the car also stood dorment and also running idle a while). Then came the problem. I'm pretty positive i've removed all of the cruise control's vacuum lines, and electronic wires, but not the brain though. When i push my screwdriver HARD against the throttle plate, the car does NOT accelerate, but as soon as i let go, the plate opens and the car "floors it".

- What creates/controlles the vacuum?
- Shoulden't the engine stall before it sucks open the throttle plate?
- Should the cruise control åpen the throttle plate with vacuum?
- Anyone know the placement or the look of the cruise control computer?

I am grateful of any help.

The cruise control opens the throttle via a secondary cable which runs from the unit to the throttle body! Have you removed this as well, if not that could be your problem! There's nothing else on these vans that I can think of that would account for this!