m50nv (auto e34) into 89 325i, cranks but no start

[FreedS4]

Yet another story of an m50 swap that will crank but not start and I'm looking to all of you for some help.

Just finished getting everything hooked up on my m50nv/g260 swap and it will crank but not start. I'm not getting spark or fuel. If I jumper pin 30 and pin 87 on the fuel pump relay base the fuel pump runs, filling the injector rail. I've tried various other relays and none work, so it doesn't appear to be a relay issue that is causing my fuel pump to not activate when starting.

I pulled a spark plug and tested it out of the head and I wasn't getting spark. I checked the resistance on the coils and they are within the proper ohm range. I've got all of my grounds connected and have triple checked my x20-c101 pinout. I replaced my CPS with one that tested in the proper ohm range.

Anything else I should be checking for or looking at solve this issue? Is there something I should be hooking up from the DME, being that it came out of an auto car? Thanks for your help. I'd really like to get this thing running before I head to Afghanistan for 6 months, four days from now.

Chris

[GunMetalGrey]

There is a ground strap right by the diagnostics plug that tripped me up the first time, I had it on the positive post which allowed it to crank but never fired. Switched it to ground and fired right up.

[FreedS4]

There is a ground strap right by the diagnostics plug that tripped me up the first time, I had it on the positive post which allowed it to crank but never fired. Switched it to ground and fired right up.

More info on this. What am I looking for? I've got two grounds (wrapped into one thick wire) at the passenger side shock tower, but that's all I see as far as available grounds. Thanks!

[FreedS4]

Just checked and I do have resistance (within the given tolerances) for both my crank and cam sensors, at the DME connector.

[FreedS4]

Went back and checked all of the pins that I had cut back to the DME connector, just to see what I don't have hooked up. All of these were a part of the connector that did not go through the x20 connector on the e34/m50nv. Let me know if any of these stand out as being something that needs to be connected somewhere or could be causing my no spark, no fuel issue.

11 - throttle valve position
48 - A/C compressor control
60 - programming voltage
64 - ignition timing intervention
65 - drive range P/N switch
85 - pressure signal
86 - compressor signal
88 - TxD diagnostic data line

[FreedS4]

Here's my pinout...1992 525i m50nv into 1989 325i

e34 ==> e30
2 ------ 10
7 ------ 11
8 ------ 12
12 ----- 4
13 ----- 13
14 ----- 14
15 ----- 15
16 ----- 2
18 ----- 18
19 ----- 16
20 ----- 9
21 ----- 7
22 ----- 6
23 ----- 5
24 ----- 8
25 ----- 1

[FreedS4]

I suppose a bad DME would cause a no spark, no fuel situation. That or a bad harness, harness connector, or bad CPS. Anything else to look for?

Chris

[FreedS4]

Just tried a different DME, out a 1992 325i manual, and still nothing. It's doing the EXACT same thing, in fact. No spark and no fuel.

Chris

[FreedS4]

Someone's bound to have experience with this!

[GunMetalGrey]

Are you using the e34 harness?
Also, sorry that I didn't respond before, I forgot that I posted in here!

[jntar]

We got it fired up.

[FreedS4]

Problem: crank but no start (no fuel, no spark)

Solution: I had "drive-away protection" (pin 81 at the DME connector, pin 7 at the x20) connected to my e30 c101 "service indicator reset" (pin 11). This caused a no spark, no fuel situation. As soon as I cut pin 7 on my c101, it fired right up!

Also, in order to use the service indicator lights, I ran pin 11 on the c101 to pin 19 on the x20. Service lights fully function now!

[Pdxseth]

Old thread but I seem to be having the same exact problem, all my wiring has been double and triple checked. Blah blah blah same thing problem.

I'm confused about why you would have ews(drive away protection) on an m50nv any car with ews would have vanos. Is this actually referring to the obc immobilized maybe? Wich from my understanding would cut fuel and spark. The diagram I used said to hook up pin 7 on the x20 to whatever. I cut the wire at pin 7 and it seemed like my car was about to fire but by that time I ran out of juice. I'm at work now. I'm wondering if you can lead me to your source of information so I can look more into this while I'm at work tonight.