On Thu, 8 Aug 1996 Philip E. Barnes wrote: (I'm a bit behind !)
> My first reaction to your problem is to say that this testing fault is not
> your problem at all. Why should you be concerned if the machine is unable
> to control your car? That is not the solution to your problem of getting
> your car tested, though. I guess I'd like to know what this machine does
> once it seizes hold of your engine.
I think one of the test these machines do is to cut out one cylinder at
a time and measure the percentage fall in rpm. This gives some
indication as to whether all the cylinders are producing the same
power. It's a quicker version of doing a compression test, and
checks more of the system. So that's why the engine tester needs to
be able to kill the engine, or at least kill the power to one cylinder
at a time. I guess it does this by shorting the coil during the time
the cylinder should be firing. Hence the lead to number 1 cylinder,
for timing reference.
Hope this makes some sense,
Julian.
_________________________________________________________________________
Julian Daley, Dept. Clinical Physics, Guy's Hospital, London
___________________________ j.daley@umds.ac.uk __________________________
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