Engine: 2.3 F/Inj Purge check valve needed

[SteveSarre]

Hi Luxo

I am no turbo expert, but I have a 1998 V70 T5 and am happy to learn.

I think yours was a 97, so AFAIK you cant use VIDA to monitor things like TCV duty cycle, MAF, fuel trim etc, which might makes some things more difficult.

But to better understand what is going on, it might be worth looking at these

https://www.youtube.com/watch?v=ShldMVI2_cI

https://www.swedespeed.com/threads/w...-on-t5.147427/

You can set up the wastegate actuator correctly with a vacuum gauge - ie engine not running and not "by the seat of your pants". You don't want to overboost and damage the engine.

Of course the problem might be in a number of places - there may be a vacuum leak somewhere etc
A number of sensors are involved, and the ECM may be telling the TCV to limit the boost (I think people refer to the TCV duty cycle). Or the wastegate actuator may not be correctly adjusted (which you can fix). The fat air hose to the turbo may be cracked causing a loss of pressure etc.

Let us know how you get on, and then I'll try to check mine!

HTH
Steve

[Pupbelly]

To add to this thread I too are experiencing the same as Luxobarge. So far the work done is:

• Replaced all the vacuum lines to and from the turbo to the (new) turbo control solenoid.
• New Pierburg turbo control solenoid
• New throttle position sensor
• Cataclean run through the fuel system (since my ownership the car is run on Shell V-Power)
• New battery

Prior to my ownership the following has been done in the last year:

• New turbo core
• New Forge turbo recirculation valve
• PCV system

All intercooler hoses have been checked and appear to be fine. The car has no fault codes (I have an OBD2 socket despite being a 1995 car)
It starts, runs and drives lovely but there is a serious lack of surge, in fact no surge at all. Something somewhere is holding the car back, there are no weird whooshing noises, no induction howls, just a lazy 2.3 lump that barely gets into the white portion of the boost gauge, but shows good vacuum.

My daily driver is an Impreza Turbo so I know how the car should feel to a degree but at the moment I'm feeling very disappointed with what is a really lovely car.

I'm yet to check the purge valves that Mr Barge has swapped, but surely that isn't going to set the world on fire???

My only observation after looking at the vacuum pipework coming from the area near the inlet manifold tucked behind the power steering area is that it looks like when the PCV system was done the rubber elbow has been swapped out with what looks like cotton braided line and I can't see a clip on it. Would that really make a huge difference? There is no kink in the pipe so instead of an elbow its a progressive curve back behind the inlet manifold. This could be a red herring??

The MAF is fine and has been cleaned too.

I have read on Focus ST 225 forums that there is a diaphragm in the oil filter housing which can cause issues, is this the case for the T5 and T5Rs on the basis they are the same engine? All boost issues on the Focus ST forums point to the boost control solenoid usually, but I have even tried a manual boost controller at all settings and have seen zero change. My actuator moves with a strong resistance as you would expect, so could the wastegate be stuck open a little?

For my and Luxobarge's sake can anyone offer some sense to this madness?

Any further ideas people?

Thank you in advance.
Mark

[sdg1970]

Unfortunately nowadays, this forum isn't the wealth of knowledge it once was. I guess Farcebook et al are the culprits...

Imo, the vaccuum elbow made up with generic braided line shouldn't be an issue. Usually with that one giving problems you get the dreaded P0172 code and horrendous fuel consumption. They are also not clipped on, just pushed on as I recall. You also say you have good vaccuum so that largely eliminates that one imo.

I can't remember what the one way purge valves actually do, but as I recall I think they are emissions related and will not really affect boost??? I'm not 100% sure, though I changed mine under advisement and one was certainly seized, but it did nothing to change my then boost issues. But in the scheme of things it was something else sorted and done.

I know the vac tree gasket can give occasional issues sometimes, but it's rare and I never changed mine. Robert DIY did his though and gained extra boost by doing it. Surely if that's an issue though it would give an horrendous hissing sound under max boost from such a small leak??

If I'm honest, my money is still on boost/intercooler hoses. Either that or it's ECU related which is a little beyond my remit I'm afraid. Does your car have a remap?? If so, what type and by how much does it increase boost by?? I'm not quite so familiar with the earlier 850's as the 70R etc. I know they're essentially the same car, but I believe they have different turbos and boost proclivities.

[Pupbelly]

Hello sdg1970, thank you for your input. I recall many years ago when I used to lurk on here when I had my T5 and S40 T4 there seemed to be a load of information here by some major 'anoraks'. Granted time moves on and those folk have probably moved on to other vehicles hence why I started to look recently at the Ford Focus ST forums but they seem to be mainly non technical folk who are more obsessed with remaps and dump valves.

I did wonder about the 'tree' but didn't want to faff with something that appears ok and as you say you would think there would be hissing or something.
I'm tempted to get a set of silicone intercooler hoses, but getting a litte fed up of chucking money at it willy nilly rather than having an actual purpose to change parts.

Do I have a remap? Who knows, bloody thing hasn't boosted correctly/fully since I bought the car so I'm going to assume not as the whole car is as original as the day it was built in all other areas. The car is by no means a dog, it has led a very pampered life and has been looked after based on how original everything is but as I said something is just not right. I bought the car based on it being a swift 'Q' car but it's a long way off the mark at the minute. It's as though the turbo is disconnected, but you would expect epic induction howls or the noise of the turbo spooling up if there was a gapping hole or split in the hoses somewhere.

I'm looking at it now in the carpark at work and its a lovely thing, but its not an ornament I want it to put a big smile on my face when driving it, not to be wafting around like a chauffeur.

[sdg1970]

When I found the split throttle body hose, I just bit the bullet and put D088 stuff on all air/vac/water areas. Whilst most hoses seemed ok in terms of leaks, they were old, crusty and likely original. Some were squishy and crumpling.

You say the previous owner changed the turbo core. I almost did similar when I was getting smoky starts and clouds of smoke going downhill when letting off the accelerator. I was also getting loads of codes of varying types and was ready to throw the car in the scrappie, rather than spend money on turbos, valve stem oil seals etc. Then somebody suggested changing the temperature sensor, along with the purge valves. At that time I was also getting boost issues too. The coolant temp sensor swap, purge valves and lines, along with a thermostat and pre-cat lambda sensor change sorted that issue. I kid you not. Quite how, I don't know, but it did.

Keep us informed anyway. I'll help all I can, but at present can't really say much more. Defo recheck those boost hoses though!

[Pupbelly]

sdg1970 interesting and makes sense, I guess the car is taking information from such as the coolant temperature and cat info. Makes you wonder what bit of those changes actually solved the problem? My car has had a recent thermostat supposedly and coolant. I have just changed the coolant reservoir and cap because they were the original ones that were discoloured and the cap was the old grey sort. (photos on another thread I posted on here, can't remember which one but the outlet on the expansion tank was cracked when I got the hose off, so it was well overdue being changed).

You say purge valves, plural, where is the other one located please? I know Mr Barge has swapped out the one by the radiator I believe, where is the other located?

I'm tempted to say "f" it and buy new intercooler hoses if nothing else to update the originals to futureproof the car but it's another £150+ adding to the bill...which I don't mind but I don't want a money pit!

[sdg1970]

Originally Posted by Pupbelly

You say purge valves, plural, where is the other one located please? I know Mr Barge has swapped out the one by the radiator I believe, where is the other located?

It's in the same general area - on an adjacent running vac line to the right forward part of the car as you look at it. Can't remember precisely, but it's there.

Originally Posted by Pupbelly

I'm tempted to say "f" it and buy new intercooler hoses if nothing else to update the originals to futureproof the car but it's another £150+ adding to the bill...which I don't mind but I don't want a money pit!

I guess at the end of the day it all comes down to how good the rest of the car is and what needs doing to it. I only paid £1300 for mine 4 years back and I've pretty much ironed all the major bugs out of it now.

[Luxobarge]

Thanks very much - all useful stuff.

The other purge valve is under the big solid Turbo air pipe that runs past the throttle body. I took this pipe off to thoroughly check the flexible parts, and underneath it hey presto was the other check valve. It's the same design as the more visible one on top of the radiator fan cowling. On mine the second purge valve was working OK so I put it back.

As mentioned, I doubt that these purge valves are going to have much bearing on the turbo boost issue, but I just think that while we're going through the whole vacuum system to make sure it's sound, then it's worth changing these too if they're faulty.

I got a supply of vac hose this morning, so as soon as I have time I'll replace the remaining crusty vacuum lines, and check a few other things that have been mentioned above.

Cheers

[Pupbelly]

We're on holiday from Saturday so any work on this car is on hold for a week or so. I'll have a nosey on our return, the annoying thing is that its getting darker earlier now, and getting cold too. Harrumph!

The car is great and looks superb and is a "survivor" having not been messed with. It has spent its last few years in a barn as a toy and seen very little use by a car collector so I'm happy to invest some money into it to get it back to tip top condition because I intend to use it as a semi daily driver and enjoy it.

I've spent goodness knows how much on my Impreza over the years ensuring it is mechanically near perfect and looking good. As a result 8 years on it is an absolute hoot to own and drive.

[Pupbelly]

I’ve just taken the black return valve off which is say under the intercooler hose near the radiator. I can blow and suck through it with ease so I’m guessing it’s duff and stuck open? Trying to blow through the electronic valve which is connected in line next to it and I can’t blow through that so I assume that’s shut normally and the car opens that as and when it needs to??

So I’ll replace the black in line return valve. Is there another one to look at at or is it a case of one is a manual stop/go valve and the other Bosch item is electronically controlled? Or is there another somewhere?

Green arrow suggests direction of flow according to the devices and where I blew through.