10 and ground????

[karlncas]

HI all,


My car apparently had advanced timing when I bought it but it drove very
roughly, recently I had the timing reduced and it is better but not as good
as I expected


As mentioned in a past post someone said that the 10 may need to have a
circuit with the ground for the computer to register the adjustment,


My first question is as this may be why me car is not running smooth how do
I do it?


My second question is if I have had the timing advanced will this need to be
done and if so once the timing is put back will it need to be done again?


Thanks in advance


Karl and Cassandra Blumenthal

[simple]

As mentioned in a past post someone said that the 10 may need to
have a circuit with the ground for the computer to register the
adjustment,

Connecting the TEN terminal (that's T.E.N., not '10') to ground tells
the computer not to try to control the idle speed. You need to do
this while adjusting the base idle, otherwise the computer will be
trying to counteract whatever adjustments you make. It's not telling
the computer to register anything - it's just telling the computer to
stay out of things for a moment while you adjust the mechanical bits.

The normal way of grounding the TEN terminal is by plugging a wire
into the diagnostic connector. This is a small black box (maybe 5cm
long) inside the engine bay, with diagnostic written on the top.
It's near the engine air intake, vaguely above the front left wheel
(probably somewhere different if you had a left-hand-drive car).

So, if you were concerned that maybe the grounding had been left in
place after someone had been adjusting, just have a look inside this
box - there are normally no wires between any of the terminals in the
top. The lid just hinges off - no tools required. It even has a
sticker inside the lid telling you what all the terminals are.

There's an article mentioning other use of the diagnostic connector
on the club website:
http://www.mx5club.org.nz/maintenance/e ... agnostics/


Karl.

[karlncas]

Do many people have this engine diagnostic feature set up with the car
alarm? Funny question I know but after disarming the alarm it flashes for
about 10 times, could this be an indication or just my alarm

Karl and Cassandra Blumenthal

[simple]

Do many people have this engine diagnostic feature set up with the
car alarm? Funny question I know but after disarming the alarm it
flashes for about 10 times, could this be an indication or just my
alarm

I'm not aware of any useful connections that one could make between
an alarm and the diagnostic connector. Maybe you could get the alarm
to force the fuel-pump to run (that's an option in the diag
connector) & then use an ignitor to self-destruct the car when
someone breaks in, but that's probably not the best idea I've ever
had... Or you could disable the ECU idle control so that the car
doesn't idle so well, then the thief will think it's a crap car and
won't bother to steal it...

My alarm flashes a large number of times on disarm if it had been
triggered while I was away. It also has different flash sequences if
it was in valet mode (which only ever happens by accident - I never
intentionally use valet mode).


Karl.