club.liberty.asn.au

Hi guys

I have an 07 GT-B and on cold start ups there is a touch of blue smoke on start up. Car drives fine and no oil usage what so ever however a cold compression check revealed #4 was down (100) whilst the other 3 cylinders were 150. I am thinking it is a valve issue - what do you guys think? I am assuming a leak down down will show the exact picture of what is happening.

Cheers

Probably an oil control ring gummed up with varnish or a mildly cracked ringland.
Or valve clearances are out, possibly worn valve guides.

You’d want to do a warm comp/leakdown test as iirc they’re more accurate.

Consider a ThrottleHappy tune for enhanced drivability & reliability...

If you’re ready for major service eg timing belt kit, that’s possibly a good opportunity to eg check the valve clearances.

Subaru’s do have cold start oil burning potential due to the horizontal cylinder configuration... so it might be considered normal

Edits^

Only recently done timing belt.

Just started all of a sudden, no loss of power or any misfires are hesitation.

Booking in for a leak down test

Interested to see the results.

My car always used oil thanks the previous owner.
The factory service interval, the stock tune and a possibly too gentle run-in would be the obvious candidates.
Another 100k+ klm later and she uses almost 500ml oil per full tank of fuel!

Can’t wait to install and break in my spare rebuilt engine!