Hi y'all. I just purchased a 850 turbo wagon from an auction for my daughter. It ran fine until I tried to drive it home. I turned it over several times and finallly held the throttle to the floor. It started but revved to about 3500 rpms and would not idle down. I shut it off and restarted. Same thing. It idled down only after I put it in reverse. I ended up leaving it there for fear it would accelerate on its own while driving. I need some help to know if it is safe to drive it home? Then what should I look for first. Thank you for any responses.

 

Probably you could clean the throttle body first and see if you find anything holding it open. Make sure the spring works correctly and it closes.

The turbos have a lot of plumbing from the MAF to the throttle. They tend to get holes in the rubber parts of that plumbing, which will cause the MAF to be wrong. Naturally that would set a check engine light. Good thing to inspect when you pick up a cheap turbo.

Idle speed is controlled by a throttle bypass valve that has rubber hoses going to it about 1" in outside diameter. It's right in front of the throttle. Personally I have found these to be really reliable.

 

Thanks firebirdparts! I will look into that. I did decide to drive it home and it ran just fine. I later restarted it and it idled fine. It does have a check engine light on. Will check codes later and respond. Thanks again.

 

I would take it to Autozone and have them read the codes and go from there..

 

if the 850 is a 94/95 you can read/clear codes using the OBDI port under the hood. Instructions can be found at volvotips.com

 

to the forum renov8r

What year is it ??