Could HPL clean too well for my car's problem?

[notharry]

I have had remarkable results from the Mobil 1 5w30 extended performance regular. obviously you cannot fix broken or worn out with oil. Short 5000 mile or less OCI. Get it hot and city driving wont do it. Take a trip to the mountains a few times. Heat cycles, a few short near WOT events at random. Bore scope the holes. Could be valve guides or anything. Some things get better with less carbon and some will get worse. Go up to 5w40 or15w40 if needed to "test". It wont hurt anything. I have used 0w40 oil and its great. Some say it breaks down and sludges up more than others IDK as ive never had an issue and still use it.. My experience with boutique brands it low. Don't use oil additives as they compete with the additive package in the oil.
Subaru had this issue in their 2.5 fb engines mostly. the first place an engine will produce carbon build-up is around the hottest components. Pistons rings and exhaust valves right. long OCI on a weak ring set cannot be done effectively on a city vehicle IMo. Too many hurtful events. Cold starts, Idling, Short trips. Heat soaking, oil coking, dilution and thermal breakdown equate to end of life for the oil. Especially on a turbo engine. A highway car sure. Thats easy miles in a perfect temp range and load.

Try a mystery oil or transmission fluid and acetone soak over the weekend in the cylinders if the bore looks good. as said IF your bore is bad (ask scored or the cross hatching is gone), its end of story and only a rebuild will fix that. Not sure what your oil consumption is (i may have missed it) but a qt every 4000 is not to bad. a qt every 800 to 1000 miles is bad. a cheap usb can be had for short money on Amazon. Good luck

 

[anndel01]

HPL PCEO is $19/quart including shipping to Hawaii. HPL PPPCEO is $22/quart with shipping to Hawaii.

 

[melk]

It was a Volvo dealer. Close to $800. I don't think the original was even bad yet, it was an upsell during timing belt work. Actually I didn't even authorize it, but didn't make a fuss. I know what you mean though that they could have not checked passages.

However, hanging out at the Volvo forums and whatnot, these years of the 5-cylinder you're pretty much guaranteed to have this problem with the control rings. It's vastly more likely to be that. I've shared a lot of DMs with other 5 cylinder owners too. Many were able to get the piston / control ring warranty work as they always serviced at dealer. I am well above the 100k extension (114k), plus I don't actually consume enough. I believe my M1 0w40 and regular oil changes actually has me in a much better place. Most folks with these years of the 5 cylinder consume more than I do.

Update - HPL is on the way.

Have you got the HPL in your Volvo yet?