Eta-to-M50: Build thread

[ShowStopper]

Sounds like what happened to me josh.. i had all the same symptoms. ended up being a bad harness.

U have a adapter for ur harness or it built into the e36 harness??

[ck_taft325is]

Honestly, I wouldn't be surprised if your harness is scabbed from another car.

[Jand3rson]

Honestly, I wouldn't be surprised if your harness is scabbed from another car.

Sigh... as much as I'm sure you'd like that to be true, I doubt it. The harness was in good shape, still attached to the engine, injector wiring and fuel rail in the stock fashion, the plastic cover on the injector wiring rail didn't even look like it had ever been removed.

The harness is hard-wired in, no adapter. Andrew wired my car's harness directly into the X20 connector. Pinouts for an '86 325es and the E34 525i were used.

It sounds to me like what Wh33lhop and Yoshi are saying, that the ECU isn't getting power and trying to start the car. If the fuel pump replay works when I jump it, but not with 2 other known good relays in place, the relay is not getting a signal from the ECU to fire the injectors and start the car.

Andrew is on his way over right now, and we are going to get to the bottom of this.

[cramer]

If the FP relay isn't getting power its either in the wiring or the DME isn't sending a signal to the relay. If you aren't getting spark either, I'd suspect the DME. Now it's down to tracing out which sensor isn't working right to tell the DME the engine is trying to start.

If you are unsure of how you tested the spark, you can leave the jumper for the FP relay on so the FP is pressurized, and see if it'll start.

Good luck!

[Farbin Kaiber]

Also, a noid light, or just a test light will let you know if the injectors are getting signal. I'm thinking this is more of a signal to DME instead of power or ground to/from DME issue.

[shiboujin]

I'm too lazy to actually look at the wiring diagrams. The ECU prooobably isn't fried. I'm figuring something isn't tripping the ECU to give power to the relays. It's probably just something switched or something not hooked up. I await more info so we can figure ish out.

[dager325]

Wild guess, fuseable link off the power from battery?

[shiboujin]

Actually, with that ground wire hooked up to the pos terminal, that's VERY possible. DO IT!

[UNHCLL]

Sigh... as much as I'm sure you'd like that to be true, I doubt it. The harness was in good shape, still attached to the engine, injector wiring and fuel rail in the stock fashion, the plastic cover on the injector wiring rail didn't even look like it had ever been removed.

The harness is hard-wired in, no adapter. Andrew wired my car's harness directly into the X20 connector. Pinouts for an '86 325es and the E34 525i were used.

It sounds to me like what Wh33lhop and Yoshi are saying, that the ECU isn't getting power and trying to start the car. If the fuel pump replay works when I jump it, but not with 2 other known good relays in place, the relay is not getting a signal from the ECU to fire the injectors and start the car.

Andrew is on his way over right now, and we are going to get to the bottom of this.

Honest question... but did the e34 even get the non-vanos M50? I was under the impression that car only got the M50TU engines. E36's in 1992 got the M50NV motors?

[ck_taft325is]

Honest question... but did the e34 even get the non-vanos M50? I was under the impression that car only got the M50TU engines. E36's in 1992 got the M50NV motors?

That was my thought and the reason for my post. I was under the impression E34's only came with M50 Vanos. But, I might be wrong.

Josh, I'm sure you guys already have but have you triple checked your fuse block?

[shiboujin]

Both E34s and E36s got non vanos and vanos motors. The year range for E36s is very short.

Non vanos motors have their merits. Janderson picked it (iirc) more out of cost and availability than anything. Besides, a vanos upgrade is REALLY easy.

[bubbajan21]

According to wikipedia, 1991 - 1992 E34's got non-vanos M50's. But hey, who trusts wiki!:)

[ck_taft325is]

Well Greg gave him a fantastic deal on it.

[shiboujin]

I've personally yanked NV M50s out of both E34s and E36s.

[Jand3rson]