No spark

[Rtarh2o]

Trying to get my 86 944 turbo running again. I just replaced all belts, hoses, vacuum lines, fuel lines, plugs, rotor, cap and plug wires. Before I started all of this the car would start. Now I have everything together and it won't start?
I know enough to know it is either fuel or spark so first I cracked the fuel line at the rail and there is fuel to that point. Next I pulled a spark plug and grounded it to check for a spark while cranking, couldn't see anything.
I have checked my coil and it tests ok but is it possible to hook a spark plug to the output wire on the coil and test it that way?
I haven't checked the injectors yet either, is there an easy way to do that? With my old 924 I could just pull one injector and test it in a jar but it didn't have a fuel rail. Do you pull the entire rail with the 944 to test the injectors?
Where do I start?
Thanks in advance
Rusty

[John_AZ]

I looked at your Jan. 2 post and see you have done a lot of work on the car...


Quote:
Have to resurrect this thread as I am having the same problem! I have my 944 Turbo back together after new belts hoses, plugs, wires, cap, rotor, etc, etc. Anyway, the car had been sitting up for several years before i started on it but it did start and run when I got it. Now after all the work it will not start! I suspect the distributor cap is not on well, I got it on pretty easily at first, probably too easily but it seemed fairly solid so I thought it was good. Anyway the car still won't start so I pulled the cap off to check the rotor, it is good but I can't get the bottom screw to catch on anything! I have the long screw driver and have tried turning clock wise and counter clock wise, I can feel it try to catch on something but when I take the screw driver out the screw pops back out with it! Does it matter which way you turn the screw? Does it latch by turning up or down? It seems like it should go just a quarter turn?
Any ideas?
Rusty

Some easy things to check.
Does the tach needle bounce 1/16th of an inch when you grind the engine?

Have you used your spare DME relay or made the jumper per Clarks?

I do not check the spark plugs by grounding to the block-----severe damage may occur to the DME computer. I use a $5 (or less) PFI Noid lite to see if the injectors are getting a signal.

If the above checks out-------My guess would be the DME computer is shot.

You could continue with some other checks:
http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/484996-let-start-no-start-checklist.html

OR a shorter link:
Bennington Motorsports

GL
John

[Rtarh2o]

I have tried a new DME relay, no difference.
I also have not noticed the tach bouncing a bit, even when the car started?
What is a PFI noid light?
Thanks, anxious to get this on the road!
Rusty

[John_AZ]

The tach needle will only bounce 1/16th of an inch when you turn the key to start and engage the starter. When the car starts the needle will go to your idle rpm.
If not "bounce" check the reference sensors per Clarks. Resistance check.

Speed and Reference Sensors - Checking, Replacement, and Adjustment

PFI NOID light (for---Bosch Port fuel injection--PFI)



Will blink if the injector is getting a signal from the DME computer.

GL
John

[Rtarh2o]

Ok, I think I know what the problem is, I forgot that during the process of replacing parts there were two connectors that literally fell apart in my hands. Two of the wires were shielded wires and just being held together by a thread of a wire (don't know how the car started that way) Anyway, I replaced those connectors with generic connectors, I ran the shield as a separate wire.
I was thinking at the time I needed to remember this because I wasn't sure it was going to work that way.
Turns out the connectors were the speed and reference connectors at the back of the manifold, pretty important.
My question now is, this, is there a way to patch those wires? Can I get new connectors?
Is there a wiring diagram to make sure I even have them wired correctly? (remember they fell apart as I was working on it, not entirely sure I got them back right)
thanks
Rusty

[wild man]

Yes, there is a diagram, available at the944, IIRC. If that is one of the flywheel sensor wires, that is definitely the problem. It is always a good idea to check the connectors on those wires, if you have a no-start condition.

EDIT: Oops, I overlooked where you mentioned that those ARE the wires in question. Well there you go then, that's it!

[John_AZ]

Check the sensor resistance per Clarks (see link above).

If the resistance is bad---You can get Bosch (BMW) interchange sensors for half the price of OEM.

If you need new connector ends:
Bosch, Amp, & Weatherpack Connectors
OR check Lindsay Racing site.


Reference sensor color/connector code:



GL
John

[Rtarh2o]

John_AZ, have you replaced your connectors?
IF so, how did you deal with the shielded wire?
I opted to go with a generic connector, I am not a big fan of the OEM type connectors but I am sure I must have done the shielded wire incorrectly.
I assume the male end of the connectors has matching colored wires?
Thanks
Rusty

[930 slant nose]

Put the rotor back in

[wild man]

Being that the connectors appear to be exactly the same, I think that becoming mixed up (reversed) is always a possibility. Just something to keep in mind.

[John_AZ]

Have not replaced the connectors male or female. Replacement is not too expensive if you use the interchange. Standard 3 pole (maybe 2 pole with a sheild splice) connectors should work.

BMW reference sensor part number-need parts - Rennlist Discussion Forums

Here is a picture of the wire ends. The "blue" wire is a sheilding wire that wraps around the yellow & black under the rubber sheathing.



GL
John

[Rtarh2o]

So the blue wire (the actual shielding) attaches to a pin and goes into the connector as a wire? It then connects to the shielding on the opposite end of the connector I assume?
So on my new 3 pole connector one of the poles should be the wire shield correct?
Rusty

[wild man]

That would be correct.

[Rtarh2o]

Ok, trying to figure out the wiring still, took apart what I had done, one end of the plug is the black/yellow/shield, the other end is white/brown/shield.
Any idea which goes to which?
Rusty

[Rtarh2o]

Just a bump to see if anyone can tell me the correct wiring for the reference and speed sensors?
One end of the connector coming from the sensors has black/yellow/shielded wire
the end going to the DME is brown/white/shielded wire.
As I said, these connectors literally fell apart in my hand, I thought I got them wired correctly but now I am beginning to wonder?
I guess I can start playing with them, I know the shielded wire goes to the shielded so through process of elimination I guess I could find it.
Rusty

[Rtarh2o]

Process of elimination worked! Just swapped the wires and it started!
Happy days, might get it on the road this weekend!
Rusty