Hey all,

I'm Tyler and I recently bought a 1995 850 Turbo. I love anything with an engine, especially working on them. The 850 is my daily car however also my project. There are a few issues that I will be trying to iron out with the help of everyone here. I will be changing out the plugs today and than its on to solving some turbo issues.

Nice to meet you all!

 

Welcome to the Forum. I loved my old 850, what a great car. If you need help with the turbo issues, let us know.

 

Welcome to the forum.

 

Thanks guys! Actually once I dropped new plugs in(NGK's) it runs much smoother through quick acceleration. Before I could feel the power cutting in and out as the turbo kicked in. I'm guessing this was due to one or more cylinders not firing(reliably).
Any idea what the psi boost is on the stock turbos?
....this is all I found Volvo 850 - Wikipedia, the free encyclopedia
I have the T-5 (Turbo)

Thanks!

 

T-5, the T is for turbo haha. and normally it's varies from 8-12 if i am not mistaken.

 

ShowTek is correct. You should be getting around 10 PSI of boost.

 

Wow wasn't expecting that but I don't doubt it. Considering 1 atmosphere is about 14 psi...looking at about 24 psi going into the cylinders?

 

Not without some sleeves.

 

Hey volvo-ers,

The 850 had been running great since I posted last. Only troubles starting it every once in awhile, but letting it sit for a few minutes would always fix that. Until about a week ago I never had real problems getting it started eventually. It will no longer start. It will crank over and crank over but no signs of ignition. First guess was that it was a fuel issue but after replacing the fuel filter with no results I am broadening my search. I haven't worked with fuel injectors before and so i'm not sure how to go about checking to make sure fuel is getting to the cylinders(other than removing and smelling the plugs for fuel).

Anyway I'm looking for any advice, there has got to be someone else who has had the same issue. I appreciate any help!

-Tyler

 

Tyler,

No start could be a few things. More then likely, it is an issue with a sensor or relay. I would start with fuel system first because that is easier to test. If it is the fuel system, it can be one of three things. The fuel pump, fuel pressure regulator, or the fuel pump relay.

Start with the relay first. When you put the car in the on position (not start position), see if you hear the fuel pump. If you don't, remove the relay and put a piece of wire in it's place to jump the relay. This should turn the pump on. If the car starts, then replace the relay. If not, put the relay back and move to the fuel pressure regulator.

To test the FPR, put the car in the one position and see if you have pressure at the fuel rail. If you do, get to see if there is gas in the vacuum line connected to the FPR. If there is a gas smell in the vacuum line, or if there is no pressure, replace the fuel pressure regulator.

If all of those things seem ok, check to fuel pump. More then likely it is ok at this point but just check that it is turning on.

If all of this checks out ok, then we need to move into the electrical system. Check this stuff first though.

 

That's a solid checklist! I appreciate it fcpgroton. I will be back in town tonight, picked up a OBD reader from a friend so I can see if the computer has any useful information as well. I am almost positive that the relay is operational because I could hear the fuel spilling out(fuel filter removed) when I put the car in the on position. As for the fuel pressure regulator...I have not located it before, any hints as to where it is located is helpul I assume it is before the rail....and after the fuel pump?

Thanks,
Tyler

 

OK so some good news, some bad. Bad news first. The OBD2 reader only works with models that were made in 1996 or later, little bit of a bummer there but maybe I can find another. The good news is that I got my engine to crank over and run a little bit. It runs...but very rough. When it first cranks over it is smooth and the rpm take off for a second(nothing unusual at this point) than once it comes back to idle speed it is struggling to stay on. Mildly shakes the whole car. If I give it just a slight tap on the accelerator the rpms rush up to 2k and than come back down again.

Note that I have replaced the fuel filter, and broke a sensor(Auto parts store tells me it is a crank case pressure sensor....never heard of one of those. Also I have not replaced this sensor so the hose is not pluged in anywhere. Didn't think it would prevent the car from starting so haven't worried about it too much yet.)

Hopefully you have had a similar experience and are willing to share