2000 XC70T AWD BiG Money Burnt; No Resolution oil sludge, short trips

Vroom · Post by **Vroom** » 25 Aug 2016, 09:43

I can post far more detail, but the nuts and bolts are these:

2000 XC70T AWD, 2nd owner
Low Miles
Some garaging history, 1st owner
Oil found about pan during inspection, bought anyway
We NEVER changed fluids upon ownership (why that's bad will be clear)
Issue appeared near 1yr mark of our ownership
Engine Light On; codes thrown left'n'right
Mechanic warns of "possible sludging issue", engine functioning on just 13psi per compression test (forgive if technically imperfect)
Multiple drains performed; sludging confirmed; pressure back to near 80psi, not great but NOT 13psi
Drove fine upon release for three weeks
Upon final oil change at 500mi mark (understand this is common for this issue),
and returning home, car throws Engine Light On, nasty noises from engine,
much blue smoke, we proceed back to mechanic who then says "needs a new turbo"
Our Response: "Nope." We tread home with broken wagon.
2nd Opinion: "1st mechanic overfilled oil by some 5qt US. May have a court case."
No legal pursuit, too thin
Own Test: Performed the infamous oil pressure vacuum test with latex glove
Result: Glove promptly filled then deflated but not necessarily because of a vacuum
2nd Owner Suspicion: STiLL plugging PCV system in concert with burst cam/other seals

Q: At least three oil flushes. What could be clogging the PCV?

Thank You profoundly.

Disclaimer: Naturally, A Volvo and Forum Newb.

Post by **chrafael** » 25 Aug 2016, 10:53

The crankcase breather has to be cleaned or replaced along with the attached hoses. Changing oil does nothing. You may find this car to be too maintenance intensive (expensive) compared to other vehicles. Try having the codes read at a parts store so you can get a good overview of what you're up against. Good luck!

Post by **jblackburn** » 25 Aug 2016, 11:03

Are you saying that one of the cylinders only has 80 PSI compression?

Post by **abscate** » 25 Aug 2016, 12:18

Im guessing thats an oil pressure reading and the bottom end is torched.

"2nd Opinion: "1st mechanic overfilled oil by some 5gal US. May have a court case.""

I don't think you can fit 5 gallons in the crankcase. There is no point litigating service on a car that is past its 'reasonable service life' in any event.

Post by **tryingbe** » 25 Aug 2016, 13:26

Vroom wrote:Engine Light On; codes thrown left'n'right

Post actual codes?

Vroom wrote: car throws Engine Light On, nasty noises from engine,

Again, post actual codes. My guess would be, engine misfire detected.

Forget PCV, nasty noises usually means engine had a catastrophic failure. Time to replace engine.

Vroom wrote: Performed the infamous oil pressure vacuum test with latex glove

Glove test is for positive crankcase (blow by gas) pressure. It has nothing to do with oil pressure.

Vroom wrote: Mechanic warns of "possible sludging issue", engine functioning on just 13psi (forgive if technically imperfect)
Multiple drains performed; sludging confirmed; pressure back to near 80psi, not great but NOT 13psi

13psi/80psi of oil pressure? Or cylinder compressor test?

Sludge is formed due to infrequent oil changes.

Vroom wrote: 2nd Owner Suspicion: STiLL plugging PCV system in concert with burst cam/other seals

Q: At least three oil flushes. What could be clogging the PCV?

Again, the PCV system can be clogged and plugged and the engine wouldn't make any noise. Your engine had a catastrophic failure.

Vroom · Post by **Vroom** » 25 Aug 2016, 14:10

jblackburn wrote:Are you saying that one of the cylinders only has 80 PSI compression?

Yes. That's after the work completed. Prior to that, it was 13psi.

Yes, I realize that the crankcase is a vacuum, sorry for the typo.

Vroom · Post by **Vroom** » 25 Aug 2016, 14:19

tryingbe wrote:
Vroom wrote:Engine Light On; codes thrown left'n'right
Post actual codes?

Vroom wrote: car throws Engine Light On, nasty noises from engine,
Again, post actual codes. My guess would be, engine misfire detected.

Forget PCV, nasty noises usually means engine had a catastrophic failure. Time to replace engine.

Vroom wrote: Performed the infamous oil pressure vacuum test with latex glove
Glove test is for positive crankcase (blow by gas) pressure. It has nothing to do with oil pressure.

Vroom wrote: Mechanic warns of "possible sludging issue", engine functioning on just 13psi (forgive if technically imperfect)
Multiple drains performed; sludging confirmed; pressure back to near 80psi, not great but NOT 13psi
13psi/80psi of oil pressure? Or cylinder compressor test?

Sludge is formed due to infrequent oil changes.

Vroom wrote: 2nd Owner Suspicion: STiLL plugging PCV system in concert with burst cam/other seals

Q: At least three oil flushes. What could be clogging the PCV?
Again, the PCV system can be clogged and plugged and the engine wouldn't make any noise. Your engine had a catastrophic failure.

TryingBe: Thanks for the blow-by-blow.

Codes: Yes, that would help! Never got these from the mechanic. Yeah ... I know.

Positive Crankshaft Test: Thanks for reminding me the correct usage of the phrase.
Fixed above.

Oil Changes: The mechanic tried to explain that synthetic should be used for this
vehicle despite Volvo indicating otherwise. Seems off to me.

Thanks for all the replies.

Post by **tryingbe** » 25 Aug 2016, 14:55

Synthetic oil is excellent choice for a turbocharged vehicle. Flow easier at cold weather, better at resisting breakdown, can use longer oil change interval, and many other benefits. Still, all vehicles, oil level needs to be checked and topped up regularly.

https://mobiloil.com/en/article/car-mai ... tional-oil

Post by **FLXC90** » 25 Aug 2016, 15:14

Okay a couple questions to further frame this. You purchased the car a year ago. How many miles wee on the car then? How many did you put on it in the year you owned it?
Had the oil been changed in that year?

Sludge develops in these cars by using petroleum based oil, driving short trips, stop and go city driving, hot humid climates and extended change frequencies.

Unfortunately, the PCV system on these cars is external to the engine, so it can't purge by using seafoam or other treatments. It must be serviced like the repair database shows.
Another symptom of sludging in these motors is deposits on the backs of the valves, they prevent the valves from sealing and can worsen compression readings. Again, how many miles on this motor?

The disconcerting part is your description of bad noises. It may be too late for your current motor, and if you pay people to work on the car, it [font=]may[/font] be time for you to cut and run. On the other hand, you found MVS, a resource that could help you save your car if you want to. (if only you had found it a year ago!) I found it when I ran into troubles with my XC90 three years ago, I've been hooked ever since

This info along with codes can tell us a lot more about what you are up against. Good Luck regardless

Post by **FLXC90** » 25 Aug 2016, 15:16

Oh yeah, 80 psi at completion of work...what work was done to try to restore compression?