Bill Ball

FINALLY! An explanation even I can understand! The rest of what you wrote is Greek to me.



Nah, it's good stuff. I think you're on to something.

Schocki

Short update: the mechanic says that they implanted the motor out of an 83, complete with wiring harness and ECU's. BUT there are NO grounding point like the one's in Sean's picture. There are only to grounding point on the cam housings.

Landseer

83 ROW was CIS, wasn't it? Major diff CE panel. Looks like he's in for some entertainment.

Did they convert to LH engine management, dual distrib, etc?

On LH ROW 16V (84,85,86) the critical engine grounding points are on cam cover (2) with 1 more just behind passenger rear cam gear cover.

On LH ROW 32V 85,86, the grounding points are on both sides of rear of V of engine, kinda where Sean shows. And the final stages are grounded beneath / below right coil in vicinity of underneath 14 pin connector.

Schocki

I'm getting confused to. According to them they swapped the motor with, wiring harness and ECU's. I asked them for the engine number. It must be an 84 MY....

Schocki

Any chance for a picture of the one behind the rear cam gear cover?

Lizard928

This isnt making much sense....
1983 block doesnt have the location for the VR sensor,
1984 and newer have both the hole for the sensor as well as the ground points.

So if they were able to install a VR sensor then they were able to add the grounds to the right spot.
You say they have spark but how was it tested? Do they have the dual dizzy installed?
If they dont have the factory hole for the VR sensor, then they would have drilled the hole out. If that is the case, then it means that the distance between the sensor and the flywheel needs to be checked.

Schocki

I'm confused too. The knowledge of the mechanic is pretty good and he is experienced but not with the 928. They have been trying to get it started for nearly two weeks (without circuit diagram). The owner is frustrated about the situation, he contacted me (but I'm 1200 miles away) because they are running out of clues. I love to do puzzles like this but I need the correct information to start with.

I asked them for the engine number, let's see what they come up with. If the took the complete motor with wiring harness it must be a MY 84 or newer (I think).
Germans like to look in the title and it states the first day of registration, they often assume that this is also the model year. But as we know after summer vacation in the factory they are starting with the MY of the next year already...

JHowell37

It sounds like they're going to need wiring diagrams for the year of the car, and for the year of the engine. I'm sure they'll be able to make it work once they sink enough time into it.

Schocki

I have all wiring diagrams but I need to know 100% which engine they put in...

Landseer

84 Euro harness / 84 Euro engine, uses VR but has ground points on cam covers. But if another later harness is used, the 84 block can accept the grounds at back of valley.

Does 85 Euro 16V harness ground at back of valley

Posts 1 and 7 show grounds of importance to engine control.
http://forums.pelicanparts.com/porsc...-16v-euro.html

John Speake

No...

Schocki

Update: The motor has the following number M28 / 22 82E05150.
Pins 5, 11 and 25 have ground there is no ground connection at the back of the valley.
As I said before there is spark, but the motor does not fire up if starter fluid is used. In my opinion there should be an initial attempt of the motor to start if starter fluid is used, or am I wrong?

Landseer

So, twin dizzy, electronic fuel injection, temp II, CPS, LH, EK. 84 16V ROW.

I'll add my 2 cents again.

May not fire, if timing is way-off.
Or spark is deceptively weak.
Or no significant cylinder compression.

Check for timing gears on correct direction (possible to reverse them).
Both rotors of twin-dizzy must turn (one slaved to other, connected beneath by mini timing belt)
Also harmonic balancer (again, possible to reverse) Facing car, from front bumper, printings on balancer should be in normal reading position, not upside down.

PM your email address, I can forward the euro test plan for engine management / injection system / ground locations. (hurry, gotta get to leave for work)


Colin and John have much more savvy about the cars.
Listen to them over me! (I usually do)

John Speake

You are correct.... it should at least try to fire. Unless it is flooded...

Sounds like there is a more fundamental problem, as Landseer suggests - timing (valves or ignition) or lack of compression.

Just to recap, they are getting a 12v rpm pulse at pin 1 LH, but the fuel pump is not engaged and the injectors not firing ?

Schocki

I'm in the train from Madrid right now and running out of batteries on my Samsung.
The motor ran before, but thru changed the TB. There is compression on all right cylinders.
As far as I know there is not a clear 0 to 12 Volt impuls from the EZF to LH. What could cause this?