SaabCentral Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter #1
Have just bought a 96 model 900SE Turbo a few weeks ago and this is the first SAAB I've owned.

Anyway I've just noticed a strange knocking noise coming from the engine compartment.
When I first start the car from cold the noise doesn't seem to be there but if I take the car out for a run and then park the car up I can hear the noise when the car is idling. I can't make out if the noise rises or falls with the engine speed when idling.

The noise seems to come from the engine bay just in front of the drivers position. With the bonnet up the noise seems to be comming from an area where there is are a lot of pulley wheels but it may be in an area slighlty higher toward the bulkhead. The noise doesn't seem to be comming from the rocker cover.

The car is an absolute dream to drive and is very quiet, smooth and fast!! Infact as soon as the car starts pulling away I can't hear the noise (it may be getting drowned out). Would be greatful for any help or advice that can be given. Yeah guy's I'm worried that something may go bang!!

Many Thanx
Kev
 

·
Registered
Joined
·
4,293 Posts
Evap canister purge valve.

The ecu waits until the engine has warmed up to start cycling the valve. It is solenoid controlled just like a relay. On older cars including mine the solenoid can start to click after a few years. Inside the cabin it can sound like knocking because of the way the sound is transmitted by the metal chassis.

To check, wait until the engine has warmed up, park the car and let the engine idle. Then put your ear against the right front fender (wing), above the wheel well. You can also disable the purge valve temporarily by unplugging the electrical connector (the two hoses should remain in place). The sound should go away when unplugged.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #3
Many thanks PMI I'll give your suggestion a try Saturday.

If it does turn out to be the Evap canister purge valve should I replace it or is it the type of thing where you leave it if you can live with it?

If I do have to change it, is it and easy job?

Once again PMI many thanx for your help!!

Kev
 

·
Registered
Joined
·
4,293 Posts
I have left mine alone so far.

You can muffle the noise with something where it makes contact with the metal. Easy access, on the right hand strut tower, just out of sight under a small metal bracket, with two hoses on opposite sides and one wire connector. You have to take some care with the hose clamps, but otherwise it just takes a few minutes. Some people report cleaning it with solvent or WD40.

If it fails (mine is just clicking), I think you eventually get a CEL. Then you have to replace it if you want the evaporative emissions system to work right.

Let us know if that is what it was.
 

·
Registered
Joined
·
7 Posts
Discussion Starter #5
Thanks PMI you were spot on!!! I found the little sucker hiding away under the bracket you mentioned. All I did to check it was this was to pop the bonnet when the noise was present and I just touched it and sure enough I could feel it clicking away.

When I get a spare minute I'll probably try and silence it or clean it as you mention.

Well thanks to you PMI I can rest a little easier now!!!

Thanks Again
Kev
 
1 - 5 of 5 Posts
Top