[05_V70R]

Has this happened to anyone? Car is a 2005 with 10k on the clock - wife called and said the R had no power on the highway.... Dealer had it fixed in 20 mins...so that's the good news...what does this part cost and is the failure rate high?

TIA

 

[Needsdecaf]

Re: Blow off valve failure? (BOV, CRV, CBD??) I know it's not a true BOV ... (05_V70R)

Quote, originally posted by 05_V70R »

Has this happened to anyone? Car is a 2005 with 10k on the clock - wife called and said the R had no power on the highway.... Dealer had it fixed in 20 mins...so that's the good news...what does this part cost and is the failure rate high? TIA

Sounds like the TCV (Turbo Control Valve)? I can't imagine the wastegate control being off and on in 20 minutes.

It's a $35 part and the failure rate is high, for some reason. It's attached to the side of the airbox and has 1 electrical wire and 3(?) boost / vaccuum lines running to it.

(BTW Where else but SS can you get a response in 2 minutes!)

Modified by needsdecaf at 5:00 AM 6-22-2006

 

[05_V70R]

THANKS and no where else can you get an anwer b4 you get off line!!!

 

[tmtalpey]

Re: Blow off valve failure? (needsdecaf)

Err, the CBV is part of the turbo assembly. The CBV is fairly reliable, and isn't a 20-minute job.

You are describing the TCV (Turbo Control Valve). That part has given many an R trouble, often however it's just a hose popping off. One of those hoses goes to the CBV, btw.

Tom.

 

[05_V70R]

Ah ha! SO that would cause a no-boost condition?

 

[tmtalpey]

Re: (05_V70R)

Yep. Sticky TCV or loose hose suppresses boost. Open CBV doesn't totally suppress boost, but doesn't allow much of it either.

Tom.

 

[Needsdecaf]

Re: Blow off valve failure? (tmtalpey)

Quote, originally posted by tmtalpey »

Err, the CBV is part of the turbo assembly. The CBV is fairly reliable, and isn't a 20-minute job. Tom.

Edited, whoops! I always get them mixed up.

 

[JimLill]

Re: Blow off valve failure? (needsdecaf)

The TCV is NOT connected to the CBV. The CBV is directly connected to the intake manifold and is purely mechanical, responding to vacuum and boost.

The TCV is fed with raw boost from the compressor side of the turbo. It is a solenoid valve with a PWM signal from the ECU. Its controlled output goes to the wastegate actuator (dashpot).

It the TCV sticks open the boost will never go over ~ 4 psi. If it sticks closed (more rare) overboost will occur and a limp mode kicks in will reduced fuel as I recall.

 

[tmtalpey]

Re: Blow off valve failure? (JimLill)

I stand corrected. I thought the third hose went to the CBV. Where does it go?

Tom.

 

[gdogg16]

Re: Blow off valve failure? (tmtalpey)

Quote, originally posted by tmtalpey »

I stand corrected. I thought the third hose went to the CBV. Where does it go? Tom.

On the older models, green line comes off the compressor housing, yellow line goes to the wastegate, and blue line goes to the intake pipe.

 

[JimLill]

Re: Blow off valve failure? (tmtalpey)

Quote, originally posted by tmtalpey »

I stand corrected. I thought the third hose went to the CBV. Where does it go?

post -MAF intake pipe

 

[tmtalpey]

Re: Blow off valve failure? (JimLill)

Quote, originally posted by JimLill »

post -MAF intake pipe

So, it's dumping the bit of boost that comes through the hose, back into the intake? Hey, that means it's a little tiny CBV/diverter!

Tom.

 

[senilesurfer]

Re: Blow off valve failure? (BOV, CRV, CBD??) I know it's not a true BOV ... (05_V70R)

It's just possibke that you had same failure I had. Factory over crimped Vacuum line to wastegate. It finally failed. No codes. Engine smooth and gutless; no boost. Easy fix, just unexpected.

Another V 70 R

 

[imageomega]

Re: Blow off valve failure? (senilesurfer)

"Engine smooth and gutless; no boost"

Thats very reassuring.

As I'm new to my R, I thought the power was normal (coming from 180hp/2200lbs, so I have no idea what 300hp/3600lbs is supposed to be).

The other day though, I turned her on and it must have been working well, because it was literally A DIFFERENT CAR.

I ordered up the HD TCV from IPD, does anyone forsee problems with running the failing TCV until it comes in? Less boost won't harm anything.. right?

 

[Needsdecaf]

Re: Blow off valve failure? (imageomega)

Quote, originally posted by imageomega »

"Engine smooth and gutless; no boost" Thats very reassuring. As I'm new to my R, I thought the power was normal (coming from 180hp/2200lbs, so I have no idea what 300hp/3600lbs is supposed to be). The other day though, I turned her on and it must have been working well, because it was literally A DIFFERENT CAR. I ordered up the HD TCV from IPD, does anyone forsee problems with running the failing TCV until it comes in? Less boost won't harm anything.. right?

No, it won't harm anything. But I'd just get a stock TCV, as you're not running any kind of tune, it will be fine on your car.

 

[JimLill]

Re: Blow off valve failure? (Needsdecaf)

related info...

the line labeled Bypass Valve goes to the CBV

 

[imageomega]

Re: Blow off valve failure? (Needsdecaf)

NeedsDecaf - I will be doing the stage 1 IPD tune within 2-4 months. (and a homebrew CAI within a week or so, not that this warrants heavy duty parts)

But the real reason I got the HD TCV is because of all the forum talk about 2-6 replacements of the TCV, even running stock. IPDs should be much better=]

On an unrelated note - kudo's to vivaperformance: I ordered a 5mm spacer kit to combat wheel rub, and hawk front pads yesterday around 1pm, and my girl just signed for them.... was UPS ground too=] woohoo!