Debugging slightly low boost
#31
#33
#34
I loosened the bolts at the manifold and had the top two parts of the clamp loose. I knew a tap with a hammer would get it, but I was focusing on tapping the clamp. Once I figured out that any tap should work, I went a got a piece of metal and gave the collector a love tap. Popped right off.
#35
Up pipe replacement didn't change a thing. This isn't WOT but it shows the EBP noise.
I'm wondering if it could be the EBP sensor (I think it may be flaky anyway, but I can't created a test using compressed air to duplicate the noise).
Is it possible that it's the EBP valve?
When I had the turbo off the plate move freely and the ebp valve did seem like it had pretty good tension holding it open. How does the valve fail , could it be flaking out and partially shutting the butterfly when there's oil pressure?
[EDIT]
I managed to stick a phone in the engine by the EBP actuator. I let it idle for a few seconds and revved it up to 1500 RPMs or so. I saw NO movement.
[/EDIT]
I'm wondering if it could be the EBP sensor (I think it may be flaky anyway, but I can't created a test using compressed air to duplicate the noise).
Is it possible that it's the EBP valve?
When I had the turbo off the plate move freely and the ebp valve did seem like it had pretty good tension holding it open. How does the valve fail , could it be flaking out and partially shutting the butterfly when there's oil pressure?
[EDIT]
I managed to stick a phone in the engine by the EBP actuator. I let it idle for a few seconds and revved it up to 1500 RPMs or so. I saw NO movement.
[/EDIT]
#36
#37
Ah... I think I spotted the confusion. Those are hundreds of samples, not a dozen or so. When analyzing a WOT run, it is almost never more than about 30 samples on a fast scangauge like Torque - or 20 on a slow one like AE. A larger scale and a smaller sample will make the whole chart look smoother. I suspect your work helped, but the scaling on your graph made things look worse than they are.
#40
OK... It's official: Something ain't right. I reviewed a number of logs from several trucks and scan tools, and the lines look smoother than that when all is well. I hate to suggest a new EBP sensor (because of cost), but the armory of options now has an echo in the room.
That being said, a new sensor will not address low boost - to my knowledge.
That being said, a new sensor will not address low boost - to my knowledge.
#42
Adding Wastegate duty cycle
I have some wastegate info. These are very short WOT runs and the sampling rate is lower than on my previous charts. X-Axis is milliseconds.
I don't yet know how to interpret this, but it seemed strange to me for it to be going between zero and 99 percent like that.
I think that at 100% the waste gate is closed (so max boost) and at zero the waste gate is in max bypass mode. Is this correct?
Also is this driven by MAP, Boost, EBP or some combo?
I don't yet know how to interpret this, but it seemed strange to me for it to be going between zero and 99 percent like that.
I think that at 100% the waste gate is closed (so max boost) and at zero the waste gate is in max bypass mode. Is this correct?
Also is this driven by MAP, Boost, EBP or some combo?