Hey guys, I have a vacuum leak behind my dash and I'm trying to source what exactly is leaking behind there.

It's coming from behind the glove box and I checked both sides of the massive plug of vacuum hoses that sits behind the leak isn't coming from them. It's coming from deeper behind the dash and to the left (closer to where the vacuum hoses go through the firewall). All hoses the hoses seem to be connected from what I can see.

I was wondering if anyone knew what sits in the location that could be leaking air?

Cheers

The vacuum hoses are for the climate control box...assuming you have one.

The hose connected from the firewall to the box may have been broken over time or has fallen off or may have a hole in it. The only way to get to it easily is via dashboard removal unfortunately. If you want a quick fix...but lose climate control function, is to block the hoses from the engine bay end.

Is the green (I think its green) one connected to the heater tap in the engine bay?

And does the leak go away when you put the thing on full heat?

Hey thanks guys, I forgot I made this thread!!

Blocked the hoses and it went away.

It's strange, When I accelerate and have the fan on full, the fan speed drops down to almost nothing, also sometimes I can hear the leak giving out a high pitch squeal, the higher I accelerate the higher the pitch of the leak goes and vice versa.

I need to pull it out to chuck a manual pedal box anyway so that's not really an issue, I just need a good idea of what would be broken behind it as once I have my dash out and have found the broken part, I won't be able to drive down to the wreckers to buy it haha, unless I put my dash back together, buy the part and remove it all over again to put the new part in there!! Cbf with that lol.

Can't see that hose, is it under the manifold with all the heater hoses?

I have the same weirdness on my 95 EF Fairmont. I've been chasing a climate fault for a year. Just been in there for an hour, glovebox and dash surround off, replaced the control unit - exactly the same.

I've done all the checks from this link - documents.php?d=9 - and there are no faults or errors showing. BUT... the system will only blow air out of the face level. Will not switch to screen or feet - ever.

From what I can see my vacuum lines are all sweet but am I not looking & checking properly? Or are there critical vacuum lines behind the dash that I can't see without dash removal?

Really frustrating.

Yeah there's more behind the glovebox towards the upper left (can't/barely be seen unless dash is removed completely), which is where I think my leak is coming from. I've heard that it could be a cracked actuator but I have no idea what's back there, this is exactly why I don't want to take my dash out yet, once it's out I won't be able to turn the car on to source the leak, and I don't even know what parts I need to replace until I have the car in pieces. Such a pain haha.