Hi Mark

Technicians who have the tools/ability to make the measurement that you have, can see straight away where the problems lie. As Mike said, there is good money to be made is re-diagnosing jobs which have been 'fixed' or attempted to be fixed with suspect parts using such techniques.

The issue is imparting this information to the less well educated/experienced. I guess if you showed a waveform such as the example to the average parts rep, they may stare blankly back at you; to be fair, a 'scan and go' type garage/technician may also do the same.

The crux of the problem for many is claiming back the wasted time involved with fitting this type of part, or even just getting a credit for the part, without having to undergo weeks of waiting, and supplier 'checks & tests', which often come back as 'we couldn't find any faults - it must be your car/the ecu'; especially, when perhaps several replacements have been fitted and also failed.

A key question is who decides if a part is actually of matching quality - and how does the supplier prove their part meets this 'quality standard'? And how does the workshop easily prove that it doesn't?

I feel that as long as workshops are bearing the brunt of the cost and aggravation, and the failure/return rates for the supplier are at an acceptable level, little will change. Often with a second or third hand repair, the faulty new part just gets binned and there is no contact with the supplying motor factor.

Perhaps workshops should vote with their cash and only buy genuine? However, we need credible supply alternatives to ensure market forces come to bear and keep everyones price and, more impotantly quality, competitive.

Think back to when we had a similar problem with aftermarket Cats and p0420 DTC's. Even with the vehicle failing emissions tests and setting a trouble code (simple to understand tests, even to the layman) suppliers were initially playing hardball regarding returns of faulty new CATs.

Perhaps it's moving towards all components requiring some form certification/testing to an ISO standard or type approval?

Regards

James.