Ferrari Mailing List: FI temperature sensor on the 328 ?

[Rui Gigante (rui.gigante]

Hi listers,

after a hard period at work I've found some time today to play with and
drive the 328. Some of you might remember I suspected a problem with the
master brake cylinder, but it didn't happen again ... and the test suggested
by Jeff indicates that the booster is ok. I guess the master is just
starting to let go ...

So I've turned my attention to other matters, like the fuel injection. At
the beginning of the year I've replaced the thermo time switch because I had
a hard time starting the car when hot, and checked fuel pressures at a
certified Bosch shop. All was ok, and the car starts ok when hot, even if it
sometimes takes a bit longer than when cold.

When I came back from a very "animated" drive today, I've noticed that the
exhaust smell seemed to indicate a rich mixture. I've always been a bit
suspicious about the fact that when started cold, it never gets the rpm past
the 1,000, like I guess it should. It just idles at the same speed, cold or
warm. So I've decided to disconnect the auxiliary injector at the plenum
(engine warm), and voila, the rpm climbs to 1,400 rpm !!

That shouldn't happen, since I've checked that the thermo time switch in NOT
providing a ground path for the injector with the engine hot, but didn't
check if I had 12v at the injector ... So I guess one of two things might be
happening:

1- the injector is faulty and is always on, and someone in the past has
"tuned" the idle to compensate
2- I think there is a separate temperature sensor for the FI. If it's
faulty, then the electronics "think" the engine is always cold, and keeps
the injector on. I'm assuming in this case that the injector is actuated by
the electronics and not directly connected to the thermo time switch. And
the water temperature sender and gauge work perfectly ...

What do you guys think? Any ideias ? The car starts and drives great, but
I'm sure this is a problem I need to solve.

Rui