In cylinder pressure testing
Good evening all
i have a four cylinder Nissan That got towed into the shop for a no start. getting Compression out of radiator. Car is old and customer declined work.
we decided to break out the transducer and do a in cylinder cranking test as we are really just learning the ins and outs of this testing procedure and we had some free time . the problem is on all four cylinders I Do not see a intake vacuum pocket . Am I doing something wrong in setup?
Thank you all
If you are cranking at Wide Open Throttle there can be no vacuum in the intake. Are you cranking at WOT?
Hey Dmitriy during these test we did not have the throttle Open. The throttle plate was at a idle position. Also , we did not disable fuel now that I am thinking about it . Would that play a factor?
You won’t have much of a vacuum reading at cranking, engine speed is too slow to create a large pressure difference after the throttle plate I would encourage you to learn as much as you can about in-cylinder waveforms and testing, then graduate up to a Pico WPS500 transducer. Will work just fine with your Verus. I use my WPS with my Zeus a lot, love it. I have the SO transducers as well but…
Practice the in cylinder cranking and running compression on a known good engine to learn what good wave forms are supposed to look like.
You will not get a visible vacuum signature at cranking speed. If you are looking for a typical engine running wave form you will not get it in a cranking situation. It also looks to me that your exhaust signature is too rounded at the opening stage which may indicate a valve train problem.
Got it!! Thank you all ! Very helpful
Snap on transducer kit is not designed for in cylinder psi diagnostics and there tech support doesn’t even acknowledge the issue when calling them . I found it to be waste of money for that purpose
Interesting ! What problems have you had with snap on pressure transducer that they are not acknowleding ? Same issue I’m seeing ?