This is a real phenomenon and not a limitation of the pressure transducer Essentially everything takes time, Yup. The reason high RPM WPS tests have no real diagnostic value has to do with the physics of pressure wave propagation to the sensor. At some point the pressures in the cylinder ...
... of this engine. It simply cannot breathe fast enough as you have proven looking at the gauge in the exhaust system simultaneously with the WPS in the cylinder. Assuming the engine to be 100% Volumetric Efficient (VE) which it never will be, we should be seeing max airflow at approx. 55 ...
The Case Study is nice.
I will read it complete later, i just had a quick look.
Biggest difference is that the Polo in the Case study is
a 12 Valve with 2 CAMs, ours is a 6 Valve with only one
CAM.
... in sync in my Head is, why is there a second pressure after the Compression when snapping it, while at idle the Pattern looks fine ?? And if the WPS is not lieing, it is over 1,5 BAR !!! I thought maybe Exhaust pressure, but connection to the front O2, we can not get the Gauge to get over 1,5 ...
Hi, Yes valve bounce is a long shot, but as Kona says you might have a valve not closing correctly, i.e. burned seat. The additional pressure in the exhaust system has to be generated from somewhere, and the cylinder pressures are the creation of it, however, another long shot, has it got a EGR valv...
Hi, @kona You mean a relative Compression Test ? Or WPS Readings of each Cylinder ? The Car starts fine, idles fine, revs up fine, no error Codes set, all Readiness Monitors run - Short Term is at around -10% - so far so good .) But the Cat starts ...