4k turbo problems

Hi guys,

Got a bit of an ongoing problem with my Supe I've racked my brains and others to see what the problem is. Just wondering if any of you guys has had the same kind of problem too.

Here's my symptons...

First tubby comes online no problems whatsoever, once I get to the second tubby range 3800k I seem to lose power and my exhaust sounds like a tractor. It feels as though something is getting stuck open in a way. After starting her the next morning the car seems like normal, it's lost it's tractor exhaust noise. Another thing is my BOV sounds like normal but as soon as I go over the 4k mark it doesn't sound even on the first tubby range

I've got Envy Hybrids on at the minute, Auto and bpu and no boost controller fitted yet i've checked all the lines and intercooler connections everything seem ok. I've checked all the vsv's and found the wastegate vsv had no continuity so I changed that hoping this was the problem, but wasn't to be I've noticed that at standstill (engine running) after going over 4k my EGCV actuator rod is not fully back, i'm not sure if this could be a problem or not?

Please help

Pete

The EGCV sticking open will change the exhaust noise making it raspy like in TTC mode.

Could be that its not opening correctly either causing all the boost to dump when the IACV opens up. I think anyway. I'd try and get a 10psi airline directly onto the EGCV actuator and try stroking it, you will then see right away whats happening.

Would this have an effect on lost power though, I can only make 0.9bar max

I hate problem solving

Thats possibly 0.9bar just from the 1st tubby. When the EGCV doesnt open and the IACV does then boost pressure flows backwards through No 2 from No1 causing mayhem.

It sounds very much like the EGCV isn't opening. As Mike says this causes massive overspeed of the 1st turbo. Not good for that turbo.

I've checked the continuity of the EGCV vsv and that was fine, so is the next step to replace the actuator?

The actuators are notoriously sticky on older cars, but it's rare for one to freeze completely (not sure I've heard of it before). They normally freeze once the car has been running off boost for a while and you suddenly go for WOT. A lift off and re-apply of the gas pedal normally solves it.

Is the actuator arm still properly attached?

Yeah the arm is still attached, after hitting the 4k the arm looks like its stuck open, but when I switch my engine off it springs back open.

If the valve is still working it's got to be a problem with the VSV hasn't it?

I tried testing it through the continiuty test and all was well, i'll see if I can get a used one from somewhere and try that

Does it spring back instantly? if so then its like the power drops off the vsv letting it dump the air off the EGCV actuator but I would have thought that would have happened already once revs are brought down to idle. If gradually then I'd say it must be a sticking valve.

Or just a thought, the vsv is sticking not allowing the air to dump.

Looks like the vsv then, i'll get another one put on just to see if that makes any difference

I had thought of going to TTC mode, but would this locate the original problem?

It's worth doing for all the time it takes and will give peace of mind that No2 is ok when you see that boost level rise to normal. If you had an air supply then it would be handy, you can also remove the vsv and test it by connecting 12v onto it. Should hear it click and by blowing through the ports you will tell if its leaking air or directing air through when switched.

Without power the vsv should pass air from the inner most port to the filter exhaust port ont he back of it. With power it should direct the air from inner most port to the outer one next to it.

IIRC the TTC mod should remove the VSV from the equation. Good point and certainly worth a a try.

Edit: too slow!

Nice one well i'll give the TTC a go later on (weather dependant) and see what the results are.

Thanks for all your help guys, i'll write up the results later on tonight (just realised it's the morning )

Pete

Dont overlook your plugs if you haven't checked them already, could be a simple job of swapping them out if the old ones are shagged and save yourself the run around of removing the rest of the gubbings to check over

If TTC does solve your issue, i may have a spare VSV or 2 you can have.

If TTC does solve your issue, i may have a spare VSV or 2 you can have.

Cheers Colin, i'll keep that in mind

Right bit of an update for you all...

Went and did the TTC mod and took her out down a nice straight. I opened her up but wasn't very happy with the results, the exhaust was the same tone as the problem I was having before, raspy and like a tractor The boost gauge only went upto just under 1.0 bar and it felt like the second tubby wasn't coming online so I backed off a little. When I came back I opened the bonnet and had a check of the actuators, both the IACV and the EGCV were wide open. Is this common for TTC mode? So I knocked off the engine and they were still wide open, so I took the hose off the IACV actuator which released some pressure thus springing back the actuator rod to normal. The EGCV rod was still fully open though so I started her up again which sprung it back to it's normal position... and breathe, everyone still with me

Not sure which route to go down now (single )

The raspy noise is normal in TTC and you can tell when the EGCV opens by the noise the first time you boost in TTC.

Also in TTC its normal for the IACV & EGCV to be held open this is due to the pressure tank holding them open.

Trouble is that when you released the pressure on the IACV hose the EGCV should have gone back to closed very quickly with the IACV so you seem to have a problem with this and not so likely the VSV now.

In your pic the EGCV is wide open as is the IACV but still not getting full boost. I'm wondering if you might have a fecked EGCV with a broken ceramic plate or something as its not acting normal thats for sure.

You'll need someone more experienced than me to confirm if thats possible as I've never messed around with the internal parts of these valves.

Cheers

Mike

Looks like the EGCV actuator is knackered then, i'll have to take it into the garage and let them tinker with it, anyone got a used EGCV actuator for sale

Cheers

Pete

I'm not sure its the actuator seeing as its went wide open in TTC. I think its internal as in the valve itself seeing as your not getting full boost but I cant be sure mate.

Hopefully someone with first hand experience can shine a bit more light on this.

Ahh I get you the actual valve itself. I'm not sure where that is located but I know it'll be a full strip down of the tubbies

Hello Supradoopa...

Your problem is to repair?

Sorry for my english, i'm french....

Thanks.

My problem is a pain the arse mate

I have this problem too....

http://images3.hiboox.com/vignettes/1208/6mk58gin.jpg

Axis exhaust "2 in 1" is broken at 3800 rpm my pressure turbo fall....