Ladies & Gents.

My '94 850 (non turbo) with 134k gives off a hiss when I'm accelerating. It seems to be around the 2000 rpm mark, it's quite audible in the cabin, an dies away when you back your foot off

Sounds like a vacuum leak, and I'd love to think that it was meant to be going to the boost pressure gauge, but sadly my 850 is the non - turbo.

Any suggestions would be just great

Thanks

 

im having the same issue, but im pretty sure that its because my exhaust has 195850 holes in it lol

 

The hiss is inside the cabin?? How does the car run otherwise?

 

The hiss is audible inside the cabin, and because just how loud it is I'm thinking it is inside somewhere. All in all, the car is great and runs well, the only things that don't work are the drivers heated seat and the struts that hold the gate open.

One of the reasons I am having trouble locating the sound is the fact that it only makes the sound when the engine is under load accelerating hard, in park it doesn't do it as far as I can tell..

And like I said the sound stops when you back your foot off of the gas pedal..

Thanks for your input all

 

Are you sure it's not an exhaust leak? That would be more likely under engine load.

If you're sure it's not the exhaust and convinced it sounds a vacuum leak, try this experiment; while keeping the engine under load (and experiencing the hissing sound) touch and depress lightly the brake pedal with your left foot; see if that changes the noise at all.

 

Gdog has a good point, it could be a brake booster vacuum leak, check that or for an exhaust system leak, as since it is a non-turbo that is the only things I can think of off hand

 

Thanks guys I'll check it when I get home from work tonight.