I have been posting quite a bit in the oil forums regarding my 2006 Subaru Tribeca Ez30d H6 165k miles. Again This is a FLAT 6 and very difficult to work on without removing the engine which would not be cost effective right now.
History:
I purchased the vehicle "AS IS" from a dealership where it appeared to not smoke. They probably started it up and let it sit "x" amount of time since they had the heads up that I was coming. I started off with Rotella T6 5w-40 and an OEM Subaru filter. It smoked heavy blue smoke at startup for about 15 seconds and then stopped. It does not smoke during normal driving. Consumption was at about 1 quart every 800 miles. I'd also get a misfire code after starting it up P301, P303, P305. (Misfire for cylinders 1, 3, and 5 all on the passenger side cylinder bank).
After some advice here I did the following:
Kreen treatment for 1000 miles and then Marvel Mystery Oil/TCW-3 moving forward. Changed oil to Pennzoil Conventional High Mileage 10w-40. Replaced PCV valve with OEM one and verified that the hoses were clean. Consumption dropped to 1872 miles per quart!
Then I got greedy. Actually I wanted to protect the engine better during the cold PA/VA winters. I though that it would make sense to go with Castrol Edge HM 10w-40. To my surprise, it is acting just like it did with the Rotella T6. Same P301, P303, and P305.
I removed the oil cap and put a piece of paper on it to check for blowby and there is none.
Short of doing a very difficult to do compression test and leakdown test on this motor, I was wondering if you think this might be more valve seat/seal/stem related as opposed to rings.
I have already heard a 1000 times that a puff of blue smoke is valve stem seal related but many say rings due to the way the Subaru sits.
Can bad rings instantly cause a code on one cylinder bank like that?
Thoughts?
Thanks
History:
I purchased the vehicle "AS IS" from a dealership where it appeared to not smoke. They probably started it up and let it sit "x" amount of time since they had the heads up that I was coming. I started off with Rotella T6 5w-40 and an OEM Subaru filter. It smoked heavy blue smoke at startup for about 15 seconds and then stopped. It does not smoke during normal driving. Consumption was at about 1 quart every 800 miles. I'd also get a misfire code after starting it up P301, P303, P305. (Misfire for cylinders 1, 3, and 5 all on the passenger side cylinder bank).
After some advice here I did the following:
Kreen treatment for 1000 miles and then Marvel Mystery Oil/TCW-3 moving forward. Changed oil to Pennzoil Conventional High Mileage 10w-40. Replaced PCV valve with OEM one and verified that the hoses were clean. Consumption dropped to 1872 miles per quart!
Then I got greedy. Actually I wanted to protect the engine better during the cold PA/VA winters. I though that it would make sense to go with Castrol Edge HM 10w-40. To my surprise, it is acting just like it did with the Rotella T6. Same P301, P303, and P305.
I removed the oil cap and put a piece of paper on it to check for blowby and there is none.
Short of doing a very difficult to do compression test and leakdown test on this motor, I was wondering if you think this might be more valve seat/seal/stem related as opposed to rings.
I have already heard a 1000 times that a puff of blue smoke is valve stem seal related but many say rings due to the way the Subaru sits.
Can bad rings instantly cause a code on one cylinder bank like that?
Thoughts?
Thanks
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