Compression problems, need help troubleshooting

[volvotanager]

Bought 2004 XC70 with 197000. They said they blew the turbo. They gave me a turbo kit to rebuild that they never used.

When I did my pre-inspection test I got lazy and didn't check the compression. The PCV needs servicing as a rubber glove on the oil filler hole expanded rather than sucked in. The coolant was higher than "max" when cold.

I went for a test drive and it seemed fine. They have replaced timing belt and transmission worked. I checked the codes and got a "turbo", "knock sensor", and forget what else from the live data.

On the 50 minute drive home I blew one huge smoke cloud that totally obscured the road behind me at about 20 minutes in. The car ran a little rough but then was fine. Then I blew a much smaller puff at about 40 minutes. It didn't happen again.

I stopped to change the title and found oil dripping down the inside of the radiator on the driver's side. Not much but was noticeable.

I paid $400 for it so I could scrap it right now and not be out of pocket but the car body is good, and overall is a nice car.

So I took off turbo. I then did a compression check. When I took the cover off there was oil on the top of the engine. When I pulled the spark plugs out they were all oily and wet. None were dry and "ashy" looking. Cylinders #1, #2, and #5 were 150psi. Cylinder #3 is 90psi and Cylinder #4 is 100psi.

I am about to do a leak test to see if its head gasket, piston rings, or valves.

Question: Does a failed turbo mess up the engine? Is there any way this has nothing to do with a head gasket, piston rings or valve issues? Should I rebuild the turbo and then just run the car with SeaFoam to see if it is just messed up from oil.

[AKAMick]

Sounds like the PCV is long overdue, most likely why the turbo starved for oil and destroyed itself, too much gunk and sludge just plugging things up. "Seafoam" really? good luck with that!

[volvotanager]

Thanks. I have been reading threads for days and gunk and sludge seem to be relieved, after the cause is fixed, by using Seafood. If I fix the PCV, get the turbo back in, and turn it on, does the motor have enough heat to burn out the crap? Other than blowing a big cloud of smoke I didn't really notice anything wrong with the motor? I am about to run over to Harbor Freight to get a leak tester.

[hoonk]

seem to be relieved, after the cause is fixed, by using Seafood. If I fix the PCV, get the turbo back in, and turn it on, does the motor have enough heat to burn out the crap? Other than blowing a big cloud of smoke I didn't really notice anything wrong with the motor? I am about to run over to Harbor Freight to get a leak tester.

A Common reason a turbo fails (bearing/bushing wears - causes oil to leak directly into exhaust or intake, turbo impeller may rub against housing or seize) is lack of oil changes. (during the previous 197k miles) The Oil pickup tube in oil pan becomes clogged with granulated charcoal like substance, prevent proper oil pressure to turbo (and everything else!) Pcv system gets clogged also.

If you replace the turbo you will need to pull the oil pan, clean "sludge" from it and replace the oil pickup tube with the new plastic style, as well as many other things to check. (or your new turbo will die soon)

"Seafood" or "Seafoam" is a great product, What it does best is take money from your wallet and puts it into theirs.

The engine will burn the oil out of the cylinders and exhaust after you stop the oil leak into them - the question is - do you want to spend the time and money needed to replace the pcv system and the turbo? What other problems does the car have (BAD TRANSMISSION) that you have not discovered yet?

If enough oil has gotten into the catalytic converter and your area requires an emission inspection, the converter may be damaged also.

[volvotanager]

Thanks for the info. They gave me all the parts to rebuild the turbo. Turbo is off and on my bench for the fix.

Luckily, in my part of Ohio there are no emission inspection requirements.

The transmission scares me. I'm new to Volvos and used to Ford/Lincolns/Hondas where parts are everywhere and cheap. I'm about to do a leak check and then will decide if it's time to send this car on its way before I do anything else.

[billr99]

Thanks for the info. They gave me all the parts to rebuild the turbo. Turbo is off and on my bench for the fix.

Luckily, in my part of Ohio there are no emission inspection requirements.

The transmission scares me. I'm new to Volvos and used to Ford/Lincolns/Hondas where parts are everywhere and cheap. I'm about to do a leak check and then will decide if it's time to send this car on its way before I do anything else.

I grew up in Cincinnati and spent most of the first 35 years or so of it in Ohio and I think I can safely said, that you won't have any difficulty getting Volvo bits. I live in the middle of automotive nowhere now and I have no problems here so you won't there. All thanks to the Internet, FCP, RockAuto and all the rest.

Cheers,

Bill

[OslosisJones]

I would suspect the head gasket is the mostly likely culprit. I had oil seeping past a spark plug at only 90k before servicing PCV. Not too expensive to replace but does require a special tool to align the cams. Might be worth having an independent take care of this job.

If there are more seals that are compromised, its harder to recommend replacing all the seals, PCV service, turbo rebuild, and fluid change if there's a possibility of a compromised transmission as well. Might want to think about picking up a lower mileage salvage car and using this one for parts before scrapping.

Otherwise, make sure to give the throttle body and intake manifold a good clean while you have the front apart for the PCV system.