S52 OBD1 cranks but won't start

[hammslice]

Have you tried starting it when the fuel pump relay jumpered?

Yes I tried that to no avail.

now that i think about it i had a new cps that didnt look like the oem one and i couldnt start my car, put the oem one back on...

Hoveringuy it trying to help me work that out. It's a little complicated as I don't have a toothed vib damper on the front of the motor because it was ditched for an underdrive before I got the motor. It is a little tricky to use the stock S52 sensor but seatlecircuit.com has a solution.

Also noticed the ground that connects to the thermostat cover and runs into the fuel rail cover wasnt getting good contenuity. Probably not your problem though.

It won't hurt for me to double check that anyway. Thanks!

man, I have my fingers crossed for you!!! I keep checking back expecting success.

Thanks for the moral support in these trying times!

[hammslice]

i got the signal converter in the mail yesterday. just got done installing it. followed the test procedures and got good illumination on the LEDs. hooked in the signal wires and tried to start and it wouldn't.

http://www.youtube.com/watch?v=HmXMRWKqSDk

[hammslice]

Are there any tests I can do on the DME to see if it is the problem child? Otherwise, I'm going to start looking.

[hoveringuy]

i got the signal converter in the mail yesterday. just got done installing it. followed the test procedures and got good illumination on the LEDs. hooked in the signal wires and tried to start and it wouldn't.

http://www.youtube.com/watch?v=HmXMRWKqSDk

By the lights it was receiving the proper signal.

Are there any tests I can do on the DME to see if it is the problem child? Otherwise, I'm going to start looking.

Put a different ECU and see if that makes a difference...

[hammslice]

Been skimming for more answers... OBC code immobilizer? Anyone have an issue related to it with the same symptoms? Just trying to use the tool between my ears before I fork over more money for parts. Thanks for all the responses so far.

[e30rapidic]

I'm sure you have tripled checked all this but going back to basics here. Did you check wiring colors?

oil pressure sensor BRN/GRN or BRN/GRY
front coolant temperature sensor (ECU) BRN/RED BRN
rear coolant temperature sensor (Gauge Sensor) BRN/YEL BRN/VIO
crank position sensor YEL
cam position sensor YEL RED/WHT BRN/ORG
VANOS solenoid RED/WHT GRN/BLU
knock sensor, 1-3 BLK NCA DME PIN 70
knock sensor, 4-6 BLK NCA DME PIN 69
throttle position sensor (TPS) BRN BRN/BLK RED/YEL
intake air temperature (IAT) sensor BRN GRY
idle control valve (ICV) WHT/YEL RED/WHT WHT/GRN
Evaporative emissions valve BRN RED/WHT attach an 68 Ohm resistor to override this.


and this for my harness adapter..


C101 pin out number on left and corresponding X20 pin out number on right


pin color description m50 pin
1 blue alternator 25
2 green/yellow oil level (static) 1
3
4 brown coolant temp 12
5 brown/green oil pressure switch 23
6 green/white fused power 22
7 green ignition coil 1 big, 1 small 21
8
9
10 blue oil level (dynamic) 2
11 white/green service lights reset 7 not sure about this one???
12 grey CEL 8
13 green/violet fuel pump 13
14
15
16 white/black SRS (unused) 19
17
18 black/yellow starter 18
19
20


Do you have any extra relays that you could swap in?

My harness is hooked up and the engine is on the stand. Doubt it will help but if you need to see anything, I can snap a pic or follow a wire.

[hammslice]

here are some scans of my notes. i need to find some time to check everything again, in painstaking detail, otw i don't think i'll get this figured out.

my wife and I created these pages using the bentley manuals and the ETMs.

car is 91 325is, engine is 97 M3, harness is 94 325. i changed the x20 to c101. no adapter.

[ck_taft325is]

Awesome.

Now do it not in cursive.

[hammslice]

Awesome.

Now do it not in cursive.

haha, my plan with making all the notes was to make a PDF document that could easily be passed to future DIYers. i would obviously use a computer for that.

[hoveringuy]

That's awesome! you've done your homework.

Very few of those connections are actually needed for it to start. I think if you only had the crank sensor it would start, and with MAF, TPS run better.

[ck_taft325is]

Hehe, I seriously appreciate that though.

Being a visual person, suddenly a lot of crap makes sense regardless that I've crawled around my S50. It really makes more sense with a drawing like such. Bravo, looks neato.

[e30rapidic]

oh wow. great notes!

[jakeb]

This drawing is really cool..... Do you have it in a higher res? I would make a large print and put it on the wall in my garage.

[Jason89i]

i am a bit confused here.

x20 p7 . . . sw/vi . what did you do with this? its for the start imobilizer.

did your 94e36 x20 have (2) green wires or (1) gn and (1) sw/vi? your notes are conflicting. anyways.... if you have (2) green wires coming out of the x20, the second one (smaller) green wire on SOME harness is for the ews (drive away protection). this needs to be clipped or it will not start. might want to pull off the dme plug and check pin 66. green = drive away protection sw/vi = start immobilizer.

ews delete chip?
harness / dme from same donor?

just some thoughts.

cheers, jason

[hammslice]

Plan on further investigating immobilizer type stuff tonight. Harness and dme came together, pretty sure they were from the same car. Red label dme. Thanks for the thoughts.