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2007 Mazdaspeed 6 VIN "L" 2.3L Turbo New Engine Knock
Hello All,
Friend blew up an engine and he put a new long block in his Mazdaspeed 6. Claims there is a knock and car falls on it's face under load around 3k RPM and threw a P0012. Scoped CKP and CMP and get clean good looking square wave forms. Owner had removed and tested Oil Control Valve (OCV) (or what some refer to as the VVT valve) by applying power and watching piston retract. Then ran engine and with OCV disconnected applied power/ground and engine rough idled almost stalling as expected.
I hooked up Maxisys and with KOER at idle the OCV was at about 12%. Using control function I stepped up OCV to the next bump Maxisys had which was 32%, there was absolutely no change to engine tone. Bumped up again to about 54% then engine reacted with very rough idle, as I would expect.
My question is, shouldn't there have been some reaction on the first bump to 32%? Initial test indicated that the piston wasn't sticking. But I'm thinking maybe when oil is pushing against/through it it's weak until it gets a higher/stronger command. Or am I totally out to lunch? Thank very much.
Applying power is basically giving it 100% so even if it does stick with a small percentage increase it most likely won't show with a 100% duty cycle applied. It may still be sticking during normal operation and hotter temperatures than a bench test.
Getting involved in discussions because I have a lot to learn still.
That's pretty much what I'm thinking...do you think that I should have noticed some change to the engine when I bumped up the OCV control from 12% to 32% while it was sitting at idle? Or would that not have been enough for the engine to start "roughing" up?
Was it an actual new (reman) long block, or a 'new-to-him' used long block? In either case, did the crankshaft balancer get removed during engine installation?
I dunno that I'd expect a reaction at 32%, necessarily? Most VVT solenoids I see idle around 16%, and sit at around 45% when cruising down the road. So, the rough idle at 54% makes me feel pretty good that the solenoid, actuator and wiring are working.
Does the scan data confirm the lack of intake cam advance under load?
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