Exhaust Valves Stuck Closed (Fixed)

MGT

Member
Messages
262
Update for anyone in the future who reads this and is having a hard time with their stuck valves. All can be done lying under the car with each side jacked up slightly without heat. That's not to say heat wouldn't make it easier. I didn't have to jack up much at all as the valves are pretty easy to access.

One of mine was hard to move but not seized so I did the usual penetrating oil, wait, move, re-oil, move around more, etc. until it moved pretty freely. I was just moving the actuator 'arm' with pliers.

The other was seized solid. So penetrating oil was left on for a while and then attacked several times. What eventually got it to move was pushing the actuator arm IN to the actuator, counter intuitively (your closing it more). It only moves a MM or two. Then I put a small pry bar between the actuator arm and the actuator itself and applied gently increasing pressure - voila - open. Same as the first valve a few more rounds of penetrating oil and repeated movement then gets it moving nicely.
 

bigbob

Member
Messages
8,952
It’s a poor design and happens every winter on mine. I use WD40 Teflon oil which dries dry if that makes sense. An old shoe lace can pull down the mechanism if it is stuck closed. I find you can get easy access by lying on the floor. No need to jack the car up IMHO.
 

MGT

Member
Messages
262
A shoelace alone wouldn't free mine. Neither would my favourite length of steel wire and some leverage.

You can get under it without jacking but I wouldn't say access is easy. Maybe easy for someone a lot smaller than me!
 

Chrislaxy

New Member
Messages
27
Hi guys. Having similar issues although mine move quite freely . Just seem to close instead of open with sport button pressed. Any ideas ?
 

Zep

Moderator
Messages
9,110
It depends on what’s wrong. First of all check the vacuum pipes that connect to the valves are connected, that bits easy. The vacuum comes from the engine compartment so make sure there are no pipes loose between the front and the back. Also easy. If the solenoid is faulty it’s a pig to get to, not so easy.
 

Chrislaxy

New Member
Messages
27
Are you saying you put it in sport and it gets quieter?

seems to be loud when it starts up and I’ve checked the valves are open but soon after they seem to close regardless if in sports mode or not. Even when in MCS they still seem quiet.

Missing the growl
 

Chrislaxy

New Member
Messages
27
It depends on what’s wrong. First of all check the vacuum pipes that connect to the valves are connected, that bits easy. The vacuum comes from the engine compartment so make sure there are no pipes loose between the front and the back. Also easy. If the solenoid is faulty it’s a pig to get to, not so easy.

way above my capabilities unfortunately. Will get it in to the garage . Boohoo
 

azapa

Member
Messages
1,300
seems to be loud when it starts up and I’ve checked the valves are open but soon after they seem to close regardless if in sports mode or not. Even when in MCS they still seem quiet.

Missing the growl
they are loud when you start because vacuum has not built enough to close them yet, I'm guessing, along with the length of pipe that also has to the drawn down. I'm guessing from what you say that the solenoid valve is shot.
 

Oneball

Member
Messages
11,075
seems to be loud when it starts up and I’ve checked the valves are open but soon after they seem to close regardless if in sports mode or not. Even when in MCS they still seem quiet.

Missing the growl

Sounds like the solenoid isn’t working.

They are naturally open and closed by vacuum from the engine. So are open at start up (no vacuum) then close when it’s developed some.

When you press the sport button a solenoid shuts off the vacuum and the valves open.
 

Chrislaxy

New Member
Messages
27
they are loud when you start because vacuum has not built enough to close them yet, I'm guessing, along with the length of pipe that also has to the drawn down. I'm guessing from what you say that the solenoid valve is shot.
****. Thanks I will get it checked out.
 

Chrislaxy

New Member
Messages
27
Sounds like the solenoid isn’t working.

They are naturally open and closed by vacuum from the engine. So are open at start up (no vacuum) then close when it’s developed some.

When you press the sport button a solenoid shuts off the vacuum and the valves open.

thanks for you reply. Will get it in for a check up.
 

azapa

Member
Messages
1,300
would you recommend installing an x pipe or is there away to maybe jamb the valves open.
Those are two separate questions and issues. Yes, xpipe is great fun and very revertible to stock, not too expensive either. Big win.

For your value issue: you could just block off the vacuum pipe once disconnected and you are done! The are also aftermarket solenoids that will do it and keep it switchable. I'm guessing though, that it might be a little tiring for you, or the neighbours, to have the valves always open?
 

safrane

Member
Messages
16,748
I was of the understanding that the GTs were opend via vacuum, but the GS were the other way round?...