97 850 T-5 TCV piped up differently to earlier

[gotmeaT-5]

Does anyone know why/when Volvo decided that the TCV should be piped up differently for the 97 850 T-5 than earlier T-5's? Or has mine been piped up incorrectly

The top and bottom ports are connected in reverse to all the pictures found on other forums and around the internet Instead of the top line, green, to the compressor that line now goes to the wastegate and the bottom, yellow, goes to the compressor instead of the wastegate.

[Rnash2002]

I dont think they changed it unless you have a later bcs,i would swith them around and see what happens,but be carful because if its round the wrong way it will give you unlimited boost.
Just go out and slowley plant your foot,if it starts the creep past normal let off then you know its piped up wrong.

[gotmeaT-5]

Ok switched them around car is far more sedate and no where near as quick now or as aggressive on the boost. It's back the green on the compressor yellow to wastegate as this picture, can someone confirm that this is correct and not the reversed way which makes my boost needle go off the scale

[Rnash2002]

That is the correct way to pipe it up,so maybe you had it piped in wrong from the start.

[gotmeaT-5]

Took the car on a test run all is good at 100mph the boost gauge is reading 6-8psi fairly sure that is on the low side some one told me it should be around 11psi is this right? if so I need my turbocharger wastegate turned up a touch

855 T-5 white injectors uprated ecu rica system

[Rnash2002]

Took the car on a test run all is good at 100mph the boost gauge is reading 6-8psi fairly sure that is on the low side some one told me it should be around 11psi is this right? if so I need my turbocharger wastegate turned up a touch

855 T-5 white injectors uprated ecu rica system
If you have a mapped ecu then yes its alittle low,every standard t5 ive had was running around 6/8 psi stock but think there 9/10 stock.
Remapped should run around 16/18 psi.

[Volvostorm]

I piped up my TCV wrong, when I changed the turbo, it went well, scared me to see the boost gauge fly off the end though!

[gotmeaT-5]

I'm slightly confused on how the TCV should be piped up some are saying the picture is the correct way yet on trawling the internet there is discussions that Volvo switched the top and bottom port for some reason. When I have my cars TCV piped up according to the picture at 100mph I read 6-9psi, agree you say thats low ive heard its on the low side, yet if I pipe it up according to what is supposed to be the Volvo adjusted way reverse the yellow and green line the car changes totally the stock boost meter goes off the end of the meter car hits spark out/fuel off around 80-95mph though driveability doesnt suffer as long as I don't hit the spark out point havent tried the new boost gauge on that pipe up way yet.

If there are any traders/volvo specialists who can once an for all point me to which way the TCV should be piped up and what damage could I cause from having it piped up incorrectly

[Before anyone chimes in pointing out that the legal speed limit is 70 mph on a motorway/dual carriage way I am well aware of that and do not recommend anyone tests their T-5 at 90-100 mph on the public highway]

[Volvostorm]

This is how mine is plumbed up, mine isn't remapped though

http://www.vpcuk.org/forums/showthread.php?t=28739

[Alan M]

If your hitting fuel cut plumbed up wrong I'd say that that is not the correct way and your car is over boosting heavilly. Leave it the correct way and pressure test the system using a compressor and bung with a leak detector spray on all your joints. That way you can rule out a major leak causing your low boost issue if your remapped.

[gotmeaT-5]

Thanks will get the system pressure tested I tried the washing liquid test you suggested yesterday that didnt show any major leaks

The colours don't help me my TCV has no coloured dots like other pictures and all my pipes are silicone, all it has is a raised line by the lowest port as it sits in the shaped hanger

[Volvostorm]

Thanks will get the system pressure tested I tried the washing liquid test you suggested yesterday that didnt show any major leaks

The colours don't help me my TCV has no coloured dots like other pictures and all my pipes are silicone, all it has is a raised line by the lowest port as it sits in the shaped hanger

If I remember right, its


Yellow = Actuator - TOP
Blue = Pipe on feed to the turbo from airbox - MIDDLE
Red = Turbo compressor housing (Turbo itself) - BOTTOM

[gotmeaT-5]

Thats the way mine hits the fuel out currently its piped up taking the bolts of the TCV housing is the top

Bottom to actuator
Middle to airbox
Top to Compressor

[Rnash2002]

So basicly your hitting fuel/boost cut,that says to me you dont have a remapped ecu as with a mapped ecu they rise the boost limit,on a standard ecu boost limit is around 14 psi ish maybe alittle more or less on different cars.

[gotmeaT-5]

I'm starting to wonder that too and to give the impression something has been changed the pipes to the TCV were switched around

Or the intercooler has so many leaks in it its allowing 90% of the pressure back out somewhere but I think the former