cold start weirdness

[SJ]

From: "Kurt W. Deschler" <desch at WPI.EDU>


> > I've changed the water temperature sensor as the first part of my
shotgun
> > troubleshooting mode. No problems so far.
>
> Mine has the newer 3-pin sensor that I have been assuming was OK.
**** 3pin?  I checked the FA for your car. The temp sender is supposed to be
1 wire, P/N 049 919 501. A 4 pin temp sensor is located under the first one
P/n 034 919 369.

> I mean ECU output test 4, which cycles the cold start valve with the fuel
> pump running. I let it run through all 10 cycles twice and that gave the
> engine a good enough prime to start. Wouldn't fire at all before I did
> this. Clearly this time the engine was not getting enough fuel to start in
> the cold weather.
**** This is my conclusion also. Its not an ignition problem, but a
fuel/temp/ECU related problem.

How about rigging a temporary, momentary-on push button switch that switches
battery voltage to the cold start injector? That would be easy to route from
under the hood, around the door and the door weather stripping, and locate
it on left side of dash.
Single Pole, Double throw(SPDT) would be good to use. www.alliedelec.com . .
.part number 747-0780, PB series Pushbutton Switches.
http://www.alliedelec.com/catalog/catalogpages/200304/658.pdf?Catalog=200304
&PageNum=658

In the normal position, the cold start injector is normally wired up.
When you push in the switch, you disconnect the computer from the injector,
and hook up the battery . . .that fires up the cold start injector. When
engine starts, you release the switch.
That would kinda work like a manual choke. It would get you out of a bind,
and would help to isolate the problem.

SJ