Eta-to-M50: Build thread

[Farbin Kaiber]

Time to get out a tester and start checking at the DME?

[Jand3rson]

Ok, so I put 5 gallons in this morning, no start, just cranks. So I tried a different relay out of the fuse box for the foglights, no start, just cranks.

Just put a jumper across the terminals in place of the relay, and when I turned the key to the 1st position, I could without a doubt hear the pump come on. So what does that mean?

[cramer]

As noted above, do this first: Just put a jumper wire in place of the FP relay. If the pump kicks on, you know it's either the relay or the signal to the relay. Grab the multimeter and see if you're getting a signal when the key is on. If so, relay is bad. If not, check your wiring from the ignition to the relay.

[samiam3356]

Have you jumped the relay to make sure everything is working correctly? Next check the resistance of the Crank Sensor. Should be low 500's even though some editions of the Bently say 1200's. Make sure the chip is installed correctly after that and then I would swap DME's after that if none of that works. Massive vacuum leaks could also cause a non crank.

[CorvallisBMW]

$5 says you're out of fuel. Same thing happened to me on my m30 swap.

[LJ851]

Most electrical devices with contacts like to be active, especially ones open to the environment. E30 relays are generally pretty robust, though.

[shiboujin]

not directly.

[nando]

the relays don't get wet. Not unless you drive with your hood open..

[shiboujin]

I don't know; why did my FP relay suddenly die one day? Why did my main relay start cutting out randomly?

they're easy to test at least..

Doesn't it rain a lot in your part of the world? I guess environment makes a big deal. Do they use heavy salts on roads? That shit makes rust happy.

[mattdk318i]

same here. Ive noticed if i clean something up it ends up failing on me. I just leave it dirty until it proves itself. Then it deserves the TLC lol.

Went back and found this earlier in the thread. lol

[nando]

I don't know; why did my FP relay suddenly die one day? Why did my main relay start cutting out randomly?

they're easy to test at least..

[shiboujin]

Why would they go bad between the time he parked the car and now? Why that ONE relay? More importantly, why not grab a multi meter and find out for sure?

[nando]

I've seen 4 relays go bad. why don't you ask Luke about them too.

[shiboujin]

I've only seen 2 E30 related relays go bad in my life. And the only reason they went bad was because they were literally submerged in water for an extended period of time. There are ways to check relays without swapping them out for new ones. Did you check for power at the fuel pump?

[Wh33lhop]

Negative.

Thanks for clearing that up.