Replaced my TCV (T5)

[T5R92011]

"Under the bonnet there is a 2.5-litre turbocharged Volvo engine.. and the torque it chucks out is immense!...
Any gear, any revs, any prod on the throttle and
you get a deep bellow and a very very satisfying surg."

Jeremy Clarkson reviewing the 2.5-litre Focus ST in 2006.

At 130,000 miles, my T5 wasn't exhibiting the "Any gear, any revs" torque characteristics. I found myself waiting for it to accelerate through 2nd and 3rd. Almost like when a VVT cam isn't engaging. Was also recently overtaken by a completely stock MK3 Focus ST in a manner which would suggest my car had a problem.

I've had a Pierburg TCV sat in the shed for ages but kept putting it off as the job looks like a pain due to the location, however made myself do it yesterday.

ECU takes a while to adjust to the new TCV so didn't expect immediate improvements (24 hours). Upon first driving it, the car drove like the ECU had been reset i.e it felt strangled and worst on power than before. However took the car out and let the car get used to my driving style.

Next day, car is now producing the "any gear any revs" torque behavior and at high RPM I can actually hear the turbo hiss. Car feels quick again, and noticeably smoother in acceleration. It's worth noting that TCV is pretty much a consumable on these cars and there are recommendations to replace them after 60,000 miles.

The job is a bit of a pain, but no more so than replacing the cabin filter... Go in via the drivers side wheel arch area.

Tips when replacing:
- No need to remove the wheel arch liner.
- Remove the top bolt of the anti-roll bar drop link and move it out of the way for better access.
- You'll need a torch to see what you're doing.
- Unplug the connector from the TCV first before trying to unseat the TCV.
- Stick the handle end of a breaker bar underneath the TCV and lever downards to lift it from the metal prong that it sits on without any drama.
- Remove the right-hand pipe first as it's the shortest and restricts movement of the TCV. One that one is off, you can move the TCV closer to you when removing the other two pipes.

I used two 9mm 'Petrol hose clamps' to replace the quick release clamps on the two horizontal pipes. The top pipe is narrower so I just re-used the original clamp.