850 T5 Turbo Parts/Connects?

[mejojo]

Please refer to:

http://gone2maui.com/Pictures/DSCF4096.JPG

97 850 T-5 with 200K miles.

I am having a problem VERY similar to one discussed here in '03. That one turned out to be fuel pressure and maybe an O-Ring. No power on hard accel, trip computer under-reporting MPG, and so forth. (Just found that thread today, so more to look at at home now)

Here it is: http://www.volvoforums.org.uk/showthread.php?t=11696

In trying to work this out, the local dealer was NO help, recommending turbo replace, etc. which adds up to probably as much as the whole car is worth. However, I could demonstrate the turbo was boosting under certain accel conditions, which are basically easing into higher revs.

- In the picture, what is the name of the valve plugging into the air pipe directly before the turbo?

- I found that this valve was previously not properly fitted into the air pipe (basically hanging loose) , letting unmetered dirty air into the turbo. Performance was good for normally-aspirated engine, but stepping on it, the turbo would try to kick in and the engine would sputter. (Dealer did not notice this loosey valve.)

- In the picture, what goes on the fitting circled in white just to the right of the valve?

- As you can see, I broke the stiff plastic pipes trying to move the valve out of the way. What is the function of these 2 pipes? Since they are long and wrap around under the intake manifold and disappear, I am just fixing them back together with rubber hosing the right size to be a "sleeve" over the break.

Of course, any help would be GREATLY appreciated, especially since the dealer is clueless. Their last "diagnosis" was that the timing belt was 6 teeth out of whack. I checked it yesterday and it's right on...took photos...showed them the photos this morning and they still insisted that the timing belt was out of whack on Friday. I tell them the engine would likely not even run like that, but that holds no sway. I guess they are thinking I fixed the timing belt over the weekend and it would somehow benefit me by acting like it was always like correct. P.S. the timing belt was replaced 91K miles ago, so it's gone a LONG way 6 teeth off...LOL.


Joe

[dooby]

Originally Posted by mejojo

Please refer to:



- In the picture, what is the name of the valve plugging into the air pipe directly before the turbo?

That is part of the PCV Positive Crankcase Ventilation I believe. A search for PCV will turn up lots more info.

Originally Posted by mejojo

- I found that this valve was previously not properly fitted into the air pipe (basically hanging loose) , letting unmetered dirty air into the turbo. Performance was good for normally-aspirated engine, but stepping on it, the turbo would try to kick in and the engine would sputter. (Dealer did not notice this loosey valve.)

Not good - not sure it'd cause the exact symptoms you describe, but you're right about unmetered air etc.

Originally Posted by mejojo

- In the picture, what goes on the fitting circled in white just to the right of the valve?

Off the top of my head, I can't remember there being any connection there on my car. It almost looks as though the rubber bung fitted at the MAF end ( mass air flow meter) should instead be where the white circle is, and a short hose from the BCS (boost controller solenoid) should attach near the MAF. The BCS is normally bolted onto the side of the air box, and has 3 hoses atached to it and an electrical connector the other side.

Originally Posted by mejojo

- As you can see, I broke the stiff plastic pipes trying to move the valve out of the way. What is the function of these 2 pipes? Since they are long and wrap around under the intake manifold and disappear, I am just fixing them back together with rubber hosing the right size to be a "sleeve" over the break.

Again, search for PCV to turn up a full HowTo for fixing this properly. It will involve taking the inlet manifold off. This was one of the first jobs I did on my car, and following Jod's excellent HowTo it went fine. Maybe around $150 for genuine parts from Volvo - perhaps less from FCP Groton or similar.

Originally Posted by mejojo

Of course, any help would be GREATLY appreciated, especially since the dealer is clueless. Their last "diagnosis" was that the timing belt was 6 teeth out of whack. I checked it yesterday and it's right on...took photos...showed them the photos this morning and they still insisted that the timing belt was out of whack on Friday. I tell them the engine would likely not even run like that, but that holds no sway. I guess they are thinking I fixed the timing belt over the weekend and it would somehow benefit me by acting like it was always like correct. P.S. the timing belt was replaced 91K miles ago, so it's gone a LONG way 6 teeth off...LOL.

Good luck with them...

Cheers, Pete

[PNuT]

white circle = evap valve pipe ;-)

[dooby]

Hi PNut,

looks like it might be a V70 vs 850 thing - I was looking through old photos to find one of my rear lights (which are going on sale in a mo) and I found one showing a blanking plug where the white circle should be.

It also kinda shows that the BCS pipe does go near the MAF, but there is another blanked off stub near the MAF as well.

Not sure what all that means, mind...

Cheers, Pete

[PNuT]

pete,

i think the other pipe that is blanked off on your picture runs to the fuel pressure regulator.....

i will have a look tomorrow

[PNuT]

just had a quick look & yes the one near the turbo is an evap system pipe & the other one does run to the fuel pressure regulator system...

quite interesting really.... i need to get my head under the bonnet of an 850

[mejojo]

Dooby,

Thanks loads for the hi-qual photo....That definitely needs a plug over!

Didn't make sense for it to be open, so either there should have been something, or nothing hooked up to it! Nice to have that cleared up!!!


Joe

[mejojo]

Wonder why the problem in the referenced thread sounded similar?

Hands anyone? Bueller? Bueller?

Well, it was FUEL PRESSURE. The pump hose had slipped off the delivery fitting and was delivering a partial load.

When I had taken the dealer's foreman/master mechanic for a ride, I told him it sounded like it was starved for fuel and asked him to check the pressure. They reported it was fine. Well, that was actually KEY for me...they hadn't gotten a SINGLE thing right so far, so if they said something was one way, you could bet it was the other.

I hooked up a tire gauge to the schraeder valve and it showed 20 PSI. I extracted the fuel pump and found the hose partially off...it's a wonder it was even delivering 20 psi, really. Got a longer piece of fuel hose and did it up and it now drives like a bat out of hell....I think much better than it ever did before as a result of seating the PCV part into the turbo intake pipe.

So, I get to meet with the service manager on Thursday and tell him how a fuel pressure issue was diagnosed as turbo replacement AND the timing belt being WAY off. I hope he used to be a mechanic so he can understand the magnitude of this. Volvo will also hear about this in glorious color.

Thanks for listening, and remember:

Rev-up sputter combined with computer under-reporting MPG means FUEL PUMP issues.

Joe