Porsche928DT

I have an 85' 32V US Auto that I will not start. I overhauled the engine and now on the first crank I got a no go . I sprayed some starter fluid down the intake and tried again and she starts up for a second which means I have spark but no injection. In testing the continuity of the LH pin 13 to one of the fuel injectors I get a strange result. There is continuity on both connections to the injector. To double check that I also checked if there was continuity between the Fuel Pump Relay point 87 and pin 13 on the LH and there was. Before I start taking things apart to find where the injector wires are contacting I wanted to check with you all and make sure that this seems to be where my problem is or wether that is normal. Please fill me in!

ZEUS+

You should test fuel injector pulse with a noid lite. Do you have fuel pressure ?

Porsche928DT

I am positive I have fuel pressure. I don't have a Noid Light so I can't do that test. I just find it strange that there is continuity between both pins that connect to the Injectors. My understanding of the system, from what I've searched and wire diagrams, is that the fuel pump relay provides the +12V to the one pin while the LH brain controls the negative to the other pin and therefore I shouldn't have continuity between the two.

ZEUS+

There will be current on both sides with ign. on(relay engaged), unless cranking or running. Then the LH pulses ground.

macreel

How'd you check resistance?

Pull the injector plug and ohm the 2 contacts?
Or were all the injector connectors removed when one was ohm'ed??

G'luck.

Porsche928DT

I pulled one of the injector connectors and left the others connected then checked the continuity between the pins of that one connector which showed they were connected. I figure that somewhere in this old wire harness the two lines are contacting.

Porsche928DT

Oh and I did disconnect the battery to do the test.

ZEUS+

This is for example purpose only. A noid light eliminates so much guess work. Also a power probe will work.
http://cgi.ebay.com/ebaymotors/Injec...QQcmdZViewItem

928drvr86.5

Here you go, hope i can help you.

Bill Ball

If there is a short in any one of the injector leads, none will fire. It is quite likely that after manipulating the old connectors, you have a short inside one of the connector boots. You can try to peel them back for a look, but you are probably going to have to replace them. Anyway, look for short there.

Porsche928DT

Well I have plenty of work on the table for tomorrow (damn sun had to go down). Ill keep you all posted on the results. Thanks for the great info guys.

928drvr86.5

Sorry that drawing turned out kinda small, I'm sure you already have it though. when i did my Intake restoration two weeks ago i had 3 injector connections that were bare wire right at the end of the rubber strain relief boots that Bill mentioned.

928drvr86.5

I found another source for the Amphenol timing connectors that are used for our injector connections. I didn't look on the site very long but I didn't see a listing for the rubber boots. http://www.kayjayco.com/catPConnectors.htm

Another site for the connectors and boots

http://www.eagleday.com/elparandtool.html

Porsche928DT

I do have the diagram but I love the blue line overlays. Much nicer on the eyes . Lets see what surprises I have for me under those rubber boots tomorrow.

928drvr86.5

Don't expect them to be too much like rubber anymore.