crank no start timing case study VW

Hi Aaron, it appears to me that the exhaust timing isn’t late as described. The compression spike at overlap can only occur if both valves are closed, right?

The exhaust valve did not open on time, it opened late as the evo point hap well after 180 after bdc

But, if EVO happens after BDC wouldn't it still be open well after TDC (overlap)? If so, then that wouldn't result in a pressure spike at TDC right?

Hey scott, after looking back at this i am incorrect, indeed has a very early exhaust valve opening and you can see that due to a sharp steap expansion stroke and closes early of course as well, while the intake is still closed at 340ish causing another “compression“ stroke since the piston is going upwards on its exhaust stroke i get another compression stroke.

I am still learning these patterns but I have to agree with Mr. Brown. If the exhaust opened when you stated, then why the steep increase in pressure? Just asking.

I believe I heard you say in the video that 30-50 minutes was the time consumed for the lab scope/pressure transducer connections, analysis and determination. It appears that some disassembly was already performed. If you were faced with a similar diag, on this same or similar year, make, model, what would you expect the minimum billed time charged to the customer should be(for the diagnosis)…

I do not know why i said 30-50 minutes ahah, it took my maybe 15*^ minutes to scope this car

Check that oil , I had a matrix not to long ago with the same pattern and the exhaust cam shifted . The valves were good to go but the crank bearings were shot. Knock knock 😅