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I'm having a hell of a time trying to figure out where my boost is going.
When I accelerate hard my boost will rise to 9-10psi then just as fast drop to 1-2psi.
I spent the day tracing and fixing even the smallest leak in the hoses. Oil, plugs, coils, ECT, all filters and nearly every hose are new.
I just ran out with the VIDA and ran up the Highway to check the duty cycle on the TCV. It looks like the duty cycle is dropping off while still under full throttle. This can not be normal, right?
download/file.php?mode=view&id=35741
Anyone have experience with boost drop-off? Please help.
Thank you
Bad Boost: VIDA TCV, TPS, and O2 log
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abscate
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Re: Bad Boost: VIDA TCV, TPS, and O2 log
The CBV diaphragm could have a hole in it and is dumping too early, but usually it's hoses or an aged TCV.
How old is it? Performance drivers will replace at 100k miles. They get tired
How old is it? Performance drivers will replace at 100k miles. They get tired
1 SWMBO for 30 years
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1999 V70 T5M 56 2005 V70 NA M56 VWs BMW
2 Volvos
3 VWs
4 Careers
5 cats/dogs/gears
6 Perfect Ladies in waiting
7 Drivers
8 Boats- with a big pointy metal thing on top
1999 V70 T5M 56 2005 V70 NA M56 VWs BMW
Re: Bad Boost: VIDA TCV, TPS, and O2 log
I have no idea on age. I was thinking the same thing with the TCV. I ordered a new Pierburg from IPD w/silicone lines, should be here today.
Looking at the log I thought I wasted my money on the TCV. I'm not sure but, it does look like it is working. Just dropping off for some reason. I will post back after work when the new one is in
Looking at the log I thought I wasted my money on the TCV. I'm not sure but, it does look like it is working. Just dropping off for some reason. I will post back after work when the new one is in
Re: Bad Boost: VIDA TCV, TPS, and O2 log
I am still waiting on the USPS to drop off my TCV. I decided to log a trip and watch the cam. It seems a little erratic to me. Of course I'm used to the good ol 350, where the only "ECU" in the thing is between your ears.
Is this cam angle movement normal? If it's not, could this cause the ECU to cut boost?
download/file.php?mode=view&id=35744
It seems to bounce around a lot with boost pres. & TCV % flat .
Is this cam angle movement normal? If it's not, could this cause the ECU to cut boost?
download/file.php?mode=view&id=35744
It seems to bounce around a lot with boost pres. & TCV % flat .
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- 20170718_052243.jpg (5.25 MiB) Viewed 325 times
Re: Bad Boost: VIDA TCV, TPS, and O2 log
Solved...so far.
download/file.php?mode=view&id=35750
The new TCV came in. The red compressor line is a PITA. Went for a run and there's no surging or fluctuation, just a smooth climb to 7psi. Happy day!
download/file.php?mode=view&id=35750
The new TCV came in. The red compressor line is a PITA. Went for a run and there's no surging or fluctuation, just a smooth climb to 7psi. Happy day!
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- 20170718_173342.jpg (747.68 KiB) Viewed 290 times
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vtl
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Re: Bad Boost: VIDA TCV, TPS, and O2 log
> When I accelerate hard my boost will rise to 9-10psi then just as fast drop to 1-2psi.
Sticky TCV solenoid. I had the same with IPD HD TCV (relabeled universal TCV made in Taiwan), which failed within the first year.
Sticky TCV solenoid. I had the same with IPD HD TCV (relabeled universal TCV made in Taiwan), which failed within the first year.