MY OWN 964 no fire thread....

[Joe Bob]

Finally got hold of Timmins.....he was cranking on heads on a Sunday. Anyways, didn't want to bother him much but he gave me some directions.....

Anyways, I have constant 12v power to the DME, the relay clicks when I turn the key, I have switchable 12v power and the DME itrslef was put in another car and worked fine.

I had help over five years ago installing the engine in 83, so my memory is fuzzy. We wired the fuel pump so that it runs constantly. Timmens says that wasn't his recommendation.

Anyways, he suspects the Crank Sensor.

I see ohm test methods for two wire sensors but not three...any ideas?

[burgundyben]

The thrid wire on a crank sensor is shielding, so doesnt need testing.

Its not really easy to test a crank sensor, you need a scope to know for sure.

Are the plugs sparking?

Have you got fuel in the rails?

Have you got 12 volts at the injectors when cranking?

[Joe Bob]

Tested the CPS, and it's within spec. Was testing the circuit for the injectors and was getting NO power. Futzed with the 6 pin connector under the seat and had power there.

Went back to the engine bay and pulled the 12 pin connector and checked power at pin 8....nada. Jumpered power to it, got 12v+ and then had power to the injector.....plugged her back in and everything seemed to work. Whatever was loose is now fixed.....Hopefully..... |

As soon as the DME gets back from my friend with the other 3.6....USPS Priority Mail and they don't lose it.....I hope to be back on the road.

Hopefully....%^)~

[Joe Bob]

OH yeah...power to coils is OK....can't check spark at the plugs until the DME is back......but it looks like it was a fuel issue. With power the injectos NOW....it should clear the issue.

[Zeke]

Originally Posted by Joe Bob

.....plugged her back in and everything seemed to work. Whatever was loose is now fixed.....Hopefully..... |

As soon as the DME gets back from my friend with the other 3.6....USPS Priority Mail and they don't lose it.....I hope to be back on the road.

Hopefully....%^)~

And what did I say on the initial thread? You were in there and a wire got loose or otherwise lost continuity.

How do I know these things? Well, you do remember the 914 race car. Every time I messed around in the engine bay, something got knocked loose. That last day it cost me my 2nd race motor.

Long story.......

[Joe Bob]

Yeah, yeah......it surprised me when it didn't fire as the engine has been rock solid since I put it in. Other than the 02 sensor wearing out I've done nothing to it. and if you don't coun the a few oil leaks I fixed when the engine was out after the 915 tossed it's cookies.....

Like I said, hope it fires when Ingo sends me back the DME and it gets hooked back up.

[Joe Bob]

DME back in still no start. Pulled a plug, grounded it....no spark.....

Any ideas?

[rick-l]

Check the speed and reference senders with your ohm meter and make sure you plugged them in the right harness.

Did you bump them working on the engine?

[Joe Bob]

Yep, the crank sensor is plugged in.....I had checked the ohm resistnace when the DME was out last week.

[rick-l]

I somewhere remember this is a 3.6 out of a 964. Is this similar to my older 3.2 with a DME and two flywheel sensors?

[Joe Bob]

Just one crank sensor.

[ischmitz]

Let's stay methodical:

The DME is working fine. So that's not the issue. It leaves the sensors or power to the DME (Timmens harnes) or power to the sensors (DME harness):

First confirm (again) that pin 18 and pin 37 have +12V with the ignition in RUN and the DME disconected. Use pin 19 as GND. All this is measured in the 55-pin connector

Next, plug the DME in and verify that one of the pins inside the injector connector and both screw terminals on the coil carry +12V with the ignition switched to RUN.

If all that checks out you must be able to hear the resonance flap actuacting when you plug the DME back in and turn the ignition to RUN. If not I wouldn't even bother looking further.

If the resonance flap actuates next on the list is the crank sensor. However, you once already confirmed +3V AC while cranking. That is in line with expectations and tells me the sensor is O.K.

Ingo

[Joe Bob]

I hear the flap actuating.....where do I test for the 3v AC?

[ischmitz]

You did test and told me you saw 3V AC when we last talked - that an early onset of Altzheimer's.......

did you measure the coil and injector power +12V?

[Joe Bob]

Back pain will do it......call me if you can.

[Joe Bob]

FuchenA.....fixed it. The switched power was hooked to turnsignal fuses and had a jumper to an unused fuse.....weird. Anyways the wire was corroded and needed a new contact end be able to have full contact on the screw down.

Drove me nuts looking for it. I hooked a alligator clip onto the pin# 3, clipped it to the test light probe and grounded it. Started wiggling wires with the ignition on. When I futzed with a turn signal fused wire the light went on.....voila!

Still had to figure out what the heck the wire was doing and why it wasn't getting full power.

HAD NOTHING to do with my wiring job prior to the no start or the cleaning of the engine oil off the valve covers......

I feel reaaalllly stoopid but glad I was able to fix it. Of course I had help which I needed to diagnose WTF was wrong.

Thanks Ingo and others......

[Joe Bob]

ALSO....nothing teaches you about a electrical system better than doing a trouble shoot on another person's work. I pulled the motor, did the install but left the wiring to another. It was a package deal on the sale of my 3.0.

No complaints, I got top dollar on the sale of my old engine and help on my conversion. Should have spent more time on observation of the wiring or got a schematic.