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Engine oil additives ok?

My mechanic wants to use an engine cleaner to add to oil, then blow it all out!! It’s a 2001 Saab 9-5 with 110k miles and is starting to burn its semi-syn at the rate of 1 qt. per 1400 miles.
He says there’s no discernable leaks.
Should I let him add anything? Just keep adding the oil?

What? Any experts out there?

Any oil consumption issues should be addressed by running a compression test, both wet and dry. This test is not 100% definitive about piston ring problems but it’s all there is. There is no test for valve seals.

What I would suggest would be to add a can of Berryman B-12 or Seafoam to the engine oil and leave it in there. If this oil useage is related to piston ring oil coking there is a slight possibility these additives can cure the problem or make it ease up a bit.

Oil coked or sludged piston rings can be caused by not changing the oil regularly enough or overheating.
Piston rings that have lost their temper or are seized in the lands due to overheating will not be cured by anything.

One quart per 1400 miles is not excessive. There is no reason to believe that the engine cleaner that the mechanic proposes to put in the oil and then “blow it out” will change the oil consumption rate. In fact, there is a possibility that the oil consumption might increase after this “treatment”.
I would use the viscosity specified in your owner’s manual and keep up with the oil changes, adding a quart as necessary. You might try a different brand of oil. For some reason, certain brands seem not to burn away as quickly as other brands.

Seriously, What Exactly Is Meant By " . . . then blow it all out!!" When Referring To Engine Repair / Maintenance ?

Where is she / he (the mechanic) going to blow, how and with what, and what if anything is going to be disassembled or removed before or during the big blow out ?

Is the mechanic just referring to driving the vehicle to “blow it all out” ?


Just my personal preference, but I would never leave seafoam in the oil. If I seafoamed the oil, I’d drive it for an absolute max of 10 miles and then change the oil. Sea foam is not a lubricant, and it’s going to make the oil less of a lubricant, which to my way of thinking is a bad idea.

I’m inclined to agree with Triedaq on this one, however I do believe a compression test as suggested by OK4450 is a good idea so that if there is an anomolie it can be addressed at this time.

Should the compression test come out okay, I’d stick with regular oil changes, perhaps at an increased frequency. An additive is IMHO fine as long as the directions are followed and your expectations are realistic. Since that’s not excessive oil usage to begin with, it may not improve…and that would not suggest a problem.

Thanks for the comments: my owner’s manual says that no additive should be put in engines with turbo.
This is very puzzling, but I’m inclined to go with the current usage until it vastly deteriorates…the car is in splendid condition and I change the oil every 5k miles religiously.

SeaFoam IS a lubricant. One of the ingredients in Seafoam is a highly refined oil. I leave Seafoam in the oil all the time to free up stuck rings from carbon.


Anything that is not a lubricant is going to burn off after a while anyway and I’ve never seen a problem with leaving SF or B-12 in place.

Your owner’s manual says that because the oil is also used to lubricate and carrty heat from the turbo bearings, and that’s an extreme environment. Turbos operate at a few hundred thousand RPM and heated by the hot exhaust.

“It’s a 2001 Saab 9-5 with 110k miles and is starting to burn its semi-syn at the rate of 1 qt. per 1400 miles.”

I thought a full synthetic would be better for a turbo. maybe it’s the “semi” part being burned off??

That’s the problem with semi-synthetic oil. It’s only as good as it’s inferior component which is the regular oil. Either run full synthetic oil or run regular oil. Anything in between is a waste of money.


Could the mechanic’s recommendation is based on the possibility that the oil return line from the turbo is becoming coked up and forcing oil past the seals. If your mechanic is a Saab specialist he may be ahead of me on the situation but shooting from the hip, I would never add a lighter, more volatile ingredient to the oil of an engine with a turbo. And, FWIW, there seems to be a move from heavy “stabilizer” additives to very light “cleaning” additives in recent years. STP and Motor Honey are getting dusty on the top shelf.

A 01 SAAB 9-5 with 110K with moderate oil consumption most likely has a failing turbo or a leaking head gasket around bolt #10. If you don’t see puddles of oil on the ground, it’s the turbo. SAABs have pretty stout rings and stem seals, so unless it’s really been overheated, it’d check the turbo before you do anything with magic oil additives. You or your mechanic can run the car to operating temp, park it and remove the front pipe / cat converter (7 bolts, about 15 minutes). From there you’ll be able to see the exhaust side of the turbo impeller. If over the course of a few hours / overnight you can see oil weep onto the impeller (google it and you’ll find pix of this online) and you’ll know you need a turbo rebuild. Swedish Dynamics, Colorado Turbocharger and Ron’s Turbo in Utah are all good places to get yours rebuilt (correctly!) at a fair price. When you do the turbo, have your mechanic drop the oil pan and clean the sludge out of there and oil pump pickup screen. It’ll be a couple of hundred bucks extra to the job, but it’s ensure that engine and new turbo have plenty of oil so they can make it to 220K. Good luck!

All these great inputs are only stimulating more questions!
I’ve been told that the biggest drawback to gas with Ethanol is that it gums up parts in the engine. Some gas stations, like CostCo, have Ethanol–which I have used. Is that part of the ‘sludge’ problem, maybe?
Also…Sean01: there must be closer places than Utah to have turbo work done! (I live in the Mid-Atlantic.) :sunglasses:
Finally, is there any way to search the Car Talk programs to see whether they have ever tackled something like this?

The Car Talk search feature is a bit iffy at best.
Can Ethanol contribute to sludging? I would say yes because many factors contribute to that problem and gasoline quality is one of them. Others are the environment, engine state of tune and condition, oil type, driving habits, environmental conditions, whether the crankcase ventilation system is working properly, and so on.

I would not start fretting over a turbocharger unit just yet. In a shop setting and when an oil consumption complaint exists the first step is always, always, always, run a compression test (both dry and wet) and possibly a leakdown test as a means of checking piston ring condition.

Since there’s often misinterpretation, or even total lack of knowledge of, what compression readings are supposed to be (even by some shops) what you should be looking for is:
Compression readings of around 185ish on all cylinders.
Any low cylinders (say 165 give or take) should be retested with the wet method. If the readings jump up (say to 185) then there’s a piston ring problem.

Stuck piston rings can be caused by oil sludging, overheating, etc.
Oil consumption can also be caused by faulty valve seals. Overheating can ruin valve seals and there is no test at all for those as they’re a replace and pray item.

Kingfisher, I’m sure there are good turbo re-builders in the Mid-Atlantic region. The closest to you I know of is Swedish Dynamics, but I’m sure there are others. I have SD rebuilt turbo in my 9-5 and its working well. That said, every shop is different, but most do not have the highly specialized equipment needed to balance a turbo for 80,000 - 100,000 rpm. Here in Colorado, where I live, there is only one company in the whole state that does have the correct balancing equipment- Colorado Turbocharger. They also use cartridge balancing cradles, which ensures the most accurate balance; I’m willing to bet there are only a few of those CBCs in the United States. (Note: I have no affiliation with them or any other turbo shop). So at the end of the day, make sure whoever rebuilds your turbo uses a US-made kit, proper dynamic balancing, and I’d spring for a 360 degree oil seal (another $50) that will ensure a long life for the rebuilt unit. Personally, I’d stay far away from the $300 EBAY Chinese turbos - fix it right the first time.

As to the other comment to check the compression, definitely also a good idea, but I’d personally check the turbo first with those symptoms - 90 or 95 times out of 100, that’s the issue. Good luck!

thanks, everyone!! compression testing being done first–then we’ll see what the diagnosis is.