Automotive Forum

steve smith wrote:Hello Marcello and thank you for your detailed post.

In my opinion the pressure transducer has become as essential as a current clamp.

There may be some scepticism surrounding that comment given I work for Pico, but rest assured, from the work I have carried out with the WPS500 I can safely say I would have been lost without it.

Regarding “looking for more insight”, I am sure you have seen the case studies and watched the tutorials from your comments and the time you have spent with this post.

All I can do is share my experience with the device here and I would love others to do the same.

From a non-intrusive approach to diagnosis, the pressure transducer can provide critical pointers when evaluating intake, exhaust, and crankcase pressures/pulsations in a relatively short space of time. When you add in an ignition or injection event to your pressure waveform you can go onto identify offending cylinders with no dismantling required.

The key is evaluating what you can see in relation to other cylinders (using sync).

By disconnecting injectors and introducing air leaks etc. will assist with evaluating the effects of such intrusion, separating cause and effect.

I agree totally with your comment “I keep thinking it is much easier to make observations when you already know where the problem lies” but you can flip this around as part of the never ending learning process.

Hind sight is a powerful learning tool and I myself have not fully understood how a component has rectified a concern until I have looked back over the evidence gathered.

Reviewing waveforms before and after fix requires analysis time, but the answers are there along with the “lesson learned” ensuring you are armed and ready to resolve the next diagnostic challenge.

Using the First look sensor is going to give you an excellent insight into the efficient running of the engine and must never be discarded as an essential diagnostic tool to accompany the WPS500.

Having both devices is going to give you excellent “one hit” coverage when looking at the relationship between exhaust gas pulses and in-cylinder pressures under fault conditions, and here is where the WPS comes into its own.

With an in-cylinder waveform capture you will be able to evaluate valve timing, valve open and close events, compression loss, exhaust back pressure, intake restrictions, and peak compression via one connection to your scope to assist you with “a glimpse into the mechanics of the engine without having to start pulling things apart”.

Once again analysis is key, capturing waveforms from suspect cylinders and comparing against known good cylinders will reveal issues surrounding poorly seated valves, broken valve springs and lobe wear etc.

The WPS500 can also be used for fluid pressure measurements (static and dynamic) adding additional tests to engine running evaluation with regards to fuel pressures as just one example

I hope some of this information is of value to Marcello and others alike?

Take care……Steve

steve smith wrote:Thank you for the feedback Dario.

You have hit on an interesting point here regarding the revelations made when using the WPS pressure transducer.

Whilst you are right that for years we have used gauges for Compression, AC, Vacuum, Pressure, etc. etc. we have never had the intricate detail revealed when using the WPS.

I refer here to the in-cylinder waveform using a WPS compared to a conventional compression tester which now reveals the 4 stroke cycle events (Conventional compression tester reveals peak pressure only)

Moving onto intake manifold pressure waveforms compared to a vacuum gauge, we can see the operation of the valve train and the effects of misfires upon manifold pressure thanks to the resolution of the scope and the response time of the WPS.

The WPS is one of those tools becomes ever more useful as we apply new techniques and adaptors to justify a purchase

I hope this helps, take care.......Steve