Now that I have the transmision fixed no my daughter's '98 S70....

I drove it to the store last night and stepped on it pretty good from a stop sign. Throttle kept going to the floor and stayed there. Tapped the brakes, stomped on the brakes, verified that cruise was off, still not stopping so shift it into neutral and throttle lets up. Try to get it to happen again and could not repeat.

Did this once when she first had the car and I turned off the cruise control at the time thinking it was probably a fault related to it somehow. Since cruise was off this most recent time what (if any) other systems would force a full throttle response from the engine.

Any other thoughts,

Kirk

 

Is it a turbo car?
If so the hose at the throttle body might have swelled up and held the throttle wide open.
I had that happen to me. Shortly after that the hose blew out.

 

I should have put more description in my post. I saw your possible diagnosis in a little searching after I posted. This car is not a turbo. Issue does not seem to crop up very often, but I can come up with a few instances where I hope it does not happen and since it is primarily my daughter's car would like to either get it diagnosed and fixed or come up with a work-around. Thought I might have done that by turning the cruise off, but apparently not.

Kirk

 

Throttle body dirty?

 

TB could be dirty. Car is a '98 w/ 256k on the clock. My FIL said he had cleaned it not too long ago, but I guess it won't take much to go over it again. Would that actually cause the pedal to be "taken away" from me? I can see where that would cause a "sticky" throttle response, but in this case pedal actually was pulled to the floor beyond where I had taken it, thus my thoughts regarding cruise.

As Usual Thanks for the help,

Kirk

 

It usually would not. But I guess it could be possible.
I would think cruise as well. Does she ever use the cruise?
If not to test remove the vacuum line from the pump and see if it happens again.
The pump is under the battery tray towards the front of the car.

 

Yeah... that really does sound like a cruise issue... maybe the vacuum release in the cruise control unit is sticky/weak. If that's the case, you'd need to get a new cruise control unit... salvage yard should have one.

 

Thanks Tech and Carrots,

I doubt my daughter even knows the car has cruise. I had turned it off a few months ago when throttle first wanted to run away and it was off the other night when I checked as it ran away again. Issue happens so infrequently (and not necessarily repeatable) that it should be a bear to troubleshoot. I will keep looking for symptoms. If cruise was OFF, could it still be causing this problem?

Kirk

 

If the wiring shorted out from like a leaking battery yes it can.
That's why I suggested removing the hose.

 

Thinking back to the other night when throttle wanted to run away, I was taking off making a right hand turn with turn signal working. Might have to try adding turn signal into the mix of what I try to do to repeat the issue since cruise is on the same lever. Or I could just do as you suggest and disable the cruise. Only problem with that is that I just like to have stuff working properly.

Will let you know if I can isolate cause.

Kirk