component testing.

["gwells" <gwells@xxxx>]

I currently have the fuel injection system and air intake manifold
removed, to carry out maintenance and repair.
Whilst I have access to the coolant distribution pipe, it would make
sense to test otherwise inaccessible components.

1. Firstly there is theThermal vacuum control valve. According to my
books,at temperatures below 40 degrees, this allows vacuum to reach the
control pressure regulator, and this seems to happen since there is
effectively a 'circuit' between outlets D and 1 on the valve. This does
not change when you subject the valve to 40 degrees, so I assume the
valve is faulty. Also there is no flow between D and outlet 2 (to vacuum
solenoid) at any temperature.

2. Lambda thermal switch. This should, I believe, have continuity at
temperatures below 15 degrees (+/- 3degrees) and be open above that
temperature. This seems to be working OK.

3. Idle speed thermistor. At temperatures below 15 degrees, the book
says that the thermister signals the ECU module to switch the regulator
to a wider open position. At any temperature this thermister appears to
have no continuity between the two terminals on the thermistor. I assume
that this is therefore faulty.

Perhaps list members could let me have their observations on the above
tests that I have caried out and also suggest any others that I should
carry out on any other components whilst I have the opportunity.

Graham (UK) vin 17152