Susan emailed last week about a problem that we're having with her
TR4. We got a lot of great suggestions and for that we thank you!
She and I have been working on the TR4 quite a bit today and here is
where we're at. After replacing the O-rings on the jet adjustments
we screwed the jet adjustments all the way in and then backed them
back out 3 full turns. Turning the car over gives plenty of fuel up
into the main part (the area where the slide piston is) of both
cards. The problem is that it doesn't even think about firing. No
attempts to run, backfire, cough, sputter or anything.
At this point we focused in on the ignition system. We've cleaned
all of the grounds that we can find and still nothing. So, we put a
spark plug wire into the center post of the coil and grounded a spark
plug out to a known good ground. Zip, nada, nothing for spark when
it's turned over. Just so you know, at some point in this critters
life it has been converted over to electronic ignition so there are
no points or condenser in the distributor. At this point we started
checking things with a multi tester and here is what we have. If all
of this is clear as mud, please ask questions because I know just
enough about electricity to be dangerous (usually to myself). With
the ohm meter set to 200k, the negative post on coil to the frame
gives continuity (a reading of 0) with the key off but -820 with the
key on (by key on I mean the run position). On DC volts, the
positive side of coil to frame gives 12 volts with the key on and 0
with the key off. From the negative side of the coil to the positive
side of the coil gives 0 volts with the key on or off. From the
negative side of the coil to the positive side of the battery gives
12 volts with the key off and 0 volts with the key on.
Are those readings what we should expect for electronic ignition? It
seems like there should be 12 volts from the positive side of the
coil to the negative side of the coil with the key on but we're
getting a reading of 0. Is there a problem in the electronic
ignition controller? I did check the ground on the controller and
it's good. Should we scrap the electronic ignition and go back to
the original ignition with new points and condenser? Where should we
go from here?
Thanks for all of your help!