Figured it would be a long shot but who knows!
I have an 05 subaru, non turbo 2.0 litre engine (EJ201). For probably 2 years it has been making pinging noises when under very light acceleration. So light that you are on a flat road, sitting at 60k's the revs drop off to about 1,500-2,000 and you can hear a light rattle. Stomp on it a bit and some times you will get a louder clunk from what i assume is detonation. It then shuts up as i assume the knock sensor detects it and winds the timing back a little.
When i got it, i never knew you were meant to de-carbon it every service, so it went about 3 years without it, that's when i started to notice it. I have give it muliple cans of the upper engine cleaner over the last 12+ months but without any success. I am assuming it is due to carbon build up on the piston, heads or valves. It did get new plugs when the problem first started, but that made no difference. They are the ones recommended on the NGK website.
When the car is not up to operating temperature it doesn't ping at all, when it's warm is when it starts.
I have used higher octane fuel, it helps some, but it does still rattle, so i don't think it is a fuel issue.
With a timing light, i can tap the block near the knock sensor and watch the timing move, so i assume it is also working as it should.
My last resort is to pull the heads and clean any deposits in there. It needs a timing belt, so i may as well do them at the same time if it needs to be done.
Any ideas?
I have an 05 subaru, non turbo 2.0 litre engine (EJ201). For probably 2 years it has been making pinging noises when under very light acceleration. So light that you are on a flat road, sitting at 60k's the revs drop off to about 1,500-2,000 and you can hear a light rattle. Stomp on it a bit and some times you will get a louder clunk from what i assume is detonation. It then shuts up as i assume the knock sensor detects it and winds the timing back a little.
When i got it, i never knew you were meant to de-carbon it every service, so it went about 3 years without it, that's when i started to notice it. I have give it muliple cans of the upper engine cleaner over the last 12+ months but without any success. I am assuming it is due to carbon build up on the piston, heads or valves. It did get new plugs when the problem first started, but that made no difference. They are the ones recommended on the NGK website.
When the car is not up to operating temperature it doesn't ping at all, when it's warm is when it starts.
I have used higher octane fuel, it helps some, but it does still rattle, so i don't think it is a fuel issue.
With a timing light, i can tap the block near the knock sensor and watch the timing move, so i assume it is also working as it should.
My last resort is to pull the heads and clean any deposits in there. It needs a timing belt, so i may as well do them at the same time if it needs to be done.
Any ideas?