Vacuum problem? Ongoing issue

phantomD · Post by **phantomD** » Mon Dec 27, 2010 9:05 pm

Hi all,

I have been chasing a cold running problem with my Brumby for quite a while with much adjustment of my auto choke etc.

As far as I am aware, the flap for fresh/recirculated air in the blower fan works by vacuum, and probably has a leaky solenoid (not my original fan). If this is leaking, could this be causing my cold running problem?

Another symptom I have is that I can really hear a "pfissshh" noise in the blower fan area when I clutch in to change gears sometimes - related, indicative of a leak?

Cheers + thanks in advance.

Post by **TOONGA** » Tue Dec 28, 2010 8:53 am

Damo I take it you know where this vacuum line is, it sounds like one has come loose (quite common) hopefully it is the one behind the glove box.

TOONGA

Silverbullet · Post by **Silverbullet** » Tue Dec 28, 2010 3:01 pm

The mechanism for the blower flap is moved by an actuator by a vacuum line, the actuator is just a can with a rubber diaphragm in it, it's possible this could be perished?
Or, on the center console there is the two round buttons that control the flap, they are both connected by a sort of see saw arrangement with a vacuum line in and out, when my wagon had the actuator problem it turned out the vac line into the switch assembly had been disconnected.

But yeah hope its the one behind the glovebox, getting to those switches and then putting it back together again was a pain

phantomD · Post by **phantomD** » Tue Dec 28, 2010 4:51 pm

Silverbullet wrote:The mechanism for the blower flap is moved by an actuator by a vacuum line, the actuator is just a can with a rubber diaphragm in it, it's possible this could be perished?

That's exactly what I was thinking. The guy who installed my a/c removed my blower fan and installed the one out of the donor car which had been left out in the elements and perhaps not very well looked after (nice smell also). I would expect that my original blower fan can just be put back in and hooked up to the evaporator. The idle up solenoid in the engine bay is also rubbish and takes a lot of vacuum to move (to be replaced) and I think that when I turn on the a/c, the combination of that leaky diaphragm and the crappy idle up solenoid is causing a large drop in vacuum. Should I also mention that the problem only really occurs with the a/c on with a cold engine? I think we have it!

Thanks Silverbullet and TOONGA.