Hissing Sound Upon Acceleration - 89 Volvo 240 Wagon

ronb · Post by **ronb** » 18 Oct 2007, 14:25

I have recently purchased an 89 Volvo 240 with 214k miles. One thing I noticed that I have never heard/seen before (I have had an 87 and 91 and own another 91 currently) is a hissing noise that is initiated upon acceleration from a dead stop. The sound goes away after a cople of seconds and returns after stopping for red light/stop sign, etc. Any ideas?

tripleb · Post by **tripleb** » 18 Oct 2007, 22:13

Sounds possibly like a vacuum leak. If it is, you should hear it at idle.

There are vac. hoses that come into the interior of the car for climate control, cruise control, turbo boost gauge.

Some, all, or none of these might apply.

At the firewall you will see where the vac. hoses enter the cabin. You can try pinching one off at a time and see if the noise goes away, then diagnose from there.

Hope that helps.

B

waynej · Post by **waynej** » 19 Oct 2007, 14:20

Is the wagon Turbo or NA? Is the noise from inside or outside the car? If it's outside is it from the front or rear? An extremely restricted exhaust system can cause a loud hiss.

ronb · Post by **ronb** » 19 Oct 2007, 14:43

The vacuum leak is the answer...Thanks.