Re: LT5 Info.., and 1228331 stuff in general.

[Daniel Ciobota <dciobota@hiwaay.net>]

Bruce Plecan wrote:

> For those of you interested in the LT5 and it's (90 MY) ecm here's some info
> that just reached CSH, HQ..
>
> It is DIS, and the module only uses a crank signal.
> The cam signal is feed to the ecm for the SEFI.

Ah, sefi not batch fire... interesting.

> The ecm turns the power on to a set of relays (to power them up at, @
> WOT/High demand injectors), which ground thru the ecm like the first set of
> 8 do.
>

So then, it is most likely a single fuel table with very interesting pulse width
values at wot/high.  That would be _fun_ to tune.

>
> The secondary air valve is solenoid operated, so it might be progessive.
>

Yeah, I looked at a bone stock zr1 saturday, and it's a very weird looking
thing.  Also, irrelevant to John, but stock zr1's have an electric air pump.

> It drives a Engine Full Power Light  (hmm, no comment about that one)......
>

Engine full power mode is the normal mode of operation.  There is a half power
(no secondary inj/runners operating?) and valet mode (engine rev and speed
limiter).


> The "line" that looks like what would be the normal sync line to the ecm is
> a DIS Failure connection.
>

uhoh, that could spell trouble for trying to get a prom dump tonight.  John
Murphy has a factory service manual, so I'll look up the connector diagram and
see if there's some way to read the line.

> It uses a seperate ESC Module!.
>

even worse news.

>
> If the serial data line is wired like I think it is good luck on getting it
> to work.

Is it possible that the standard aldl protocol would still allow me to dump the
prom?  i think the "dump data block" command would still work the same with the
zr1, provided i can get access to the data line.  Am I wrong here?

 I plan to go over to John's tonight and play with his car, so any more info you
can come up with, especially related to the aldl interface, let me know.

Thanks,

Daniel