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In which case neither the harness nor the car has a C104 connector.
As a recap to make sure I understand the symptoms…
You have spark when cranking, but the fuel pump relay doesn’t close (i.e. no power at fuse 11) and thus the pump doesn’t run. Correct? Are the injectors firing when cranking (as proved by a noid light)? Will the engine start and run if you jumper the fuel pump relay?
That’s not entirely correct. The fuel pump turns on when we turn the key to “START” - the relay is working as expected while we’re cranking. The pump seems to be working.
We tried jumping the fuel pump relay and cranking and it didn’t make any difference.
We took a spark plug out and could definitely smell fuel from the cylinder while we were cranking. I haven’t done any fuel pressure tests yet.
We do have spark and the battery is in good shape.
So I did misunderstand. When cranking the pump is running and you have spark, but the engine does not fire. That suggests that the A/F ratio could be so far off as to prevent combustion or the cam timing is way off. A cause of that could be a large intake leak, a problem with fuel delivery, or a problem with cam timing.
I infer that there has been an engine change. In which case it is possible that the supply and return hoses have been crossed at the rail/FPR. The fuel supply hose goes directly to the rail and the return line to the FPR. Check for that by pulling the hose to the FPR off. The supply hose should be under pressure so be prepared for a fuel leak if the lines are crossed. If fuel sprays out when you pull that hose the lines are crossed. If fuel doesn’t spray out hook a hose to the FPR, lead it into a container, and briefly jumper the fuel relay. Gas should flow out of that hose when the pump is running. If it doesn’t the FPR could be plugged or the pump not producing enough pressure. The next step would be to check rail pressure. Pressure significantly higher that normal (~43psi) would mean the FPR is bad and lower would mean the pump is bad or the supply line is obstructed.
If the fuel delivery tests out the next step is to use a noid light to see if the injectors are firing. Test the injectors for cylinders 1 and 2 to check both injector banks.
If good so far, re-check cam timing and check for intake leaks.
Harbor Freight has a noid light set for not much. You could borrow mine, but by the time you paid for round trip shipping you could almost have your own.
@jlevie Thanks for the info. I’ll try all that out on Saturday. And yes, this is me being neck deep in an engine swap (If you can’t tell I’ve never done this before).
@Ranger, thanks for the offer! I’ll pick one up from Harbor Freight if I need to.
Hey guys, so I had time to check the fuel supply. I followed the test in the Bentley book, I connected a length of hose to the FPR and pumped fuel for 30 seconds and got pretty much 875 ml of gas, so its pretty spot on with how much gas its delivering.
I got a spark plug checker at harbor freight on plugs 1 and 2 (http://www.harborfreight.com/inline-ignition-spark-checker-69014.html that thing)- they both lit up. However, they followed a pattern of dim-dim-dim-bright, and it was a regular pattern and consistent with how it was timed.
I’m not entirely sure what a noid light is - will it provide any more diagnostic info than what I already got? (Thanks again everybody)
Hey guys, so I had time to check the fuel supply. I followed the test in the Bentley book, I connected a length of hose to the FPR and pumped fuel for 30 seconds and got pretty much 875 ml of gas, so its pretty spot on with how much gas its delivering.
I got a spark plug checker at harbor freight on plugs 1 and 2 (http://www.harborfreight.com/inline-ignition-spark-checker-69014.html that thing)- they both lit up. However, they followed a pattern of dim-dim-dim-bright, and it was a regular pattern and consistent with how it was timed.
I’m not entirely sure what a noid light is - will it provide any more diagnostic info than what I already got?
[quote=“kingofpoptart” post=68243]Hey guys, so I had time to check the fuel supply. I followed the test in the Bentley book, I connected a length of hose to the FPR and pumped fuel for 30 seconds and got pretty much 875 ml of gas, so its pretty spot on with how much gas its delivering.
I got a spark plug checker at harbor freight on plugs 1 and 2, http://www.harborfreight.com/inline-ignition-spark-checker-69014.html that thing, they both lit up. However, they followed a pattern of dim-dim-dim-bright, and it was a regular pattern and consistent with how it was timed.
I’m not entirely sure what a noid light is - will it provide any more diagnostic info than what I already got?[/quote]
Something is up, I can’t see any new posts. They all show up blank?
I’ll repost what I tried to say one more time -
Hey guys, so I had time to check the fuel supply. I followed the test in the Bentley book, I connected a length of hose to the FPR and pumped fuel for 30 seconds and got pretty much 875 ml of gas, so its pretty spot on with how much gas its delivering.
I got a spark plug checker at harbor freight on plugs 1 and 2 - they both lit up. However, they followed a pattern of dim-dim-dim-bright, and it was a regular pattern and consistent with how it was timed.
I’m not entirely sure what a noid light is - will it provide any more diagnostic info than what I already got?
Ah ha! I think it was giving me trouble with the link I tried posting.
This is the spark plug checker I got Will a noid light give me any more info that this will?
Try deleting your signature and see if anything shows up when you post. I had this problem a few weeks ago.
Actually I think it was because I was trying to post a link to harbor freight - it seemed to work if I omitted that link. Apparently the forum is bitter against harbor freight for something!
But yeah, I’ll be ordering the noid light kit pretty soon. jlevie is suggesting I still try doing a fuel pressure test, but I’ll need to buy a gauge for that - anybody have any advice on what I’ll need to run that test that might not be obvious?
While you’re at HF, buy the fuel pressure test kit too. It’s cheap.
After fighting lots of battles, I ultimately put a fuel pressure gauge on my dash. A lot of my ideas really don’t work out all that great. But having the fuel pressure gauge on the dash has been a long term winner. The dash mounted F/A meter was another idea that ended up being very helpful.
Nothing against Harbor Freight, just a hiccup in the forum software. Should be all better now. 
Good news everyone! Well, maybe… I’m just gonna be optimistic because its SOMETHING.
On Ranger’s offhanded suggestion I decided to take a look at the ignition rotor. Upon taking the distributor cap off, we saw that one or two of the metal connections look like it had been chipped away by the ignition rotor. I may have got the ignition rotor on a little off center. I’m going to order a new distributor cap soon I believe.
I attached some photos of the cap to share. You can see one of the metal connections definitely looks warn away. How do I make sure I don’t make this doesn’t happen again? Or does that just look like normal wear?
Thanks guys! I’m finally in a good mood in the garage. BEERS ALL AROUND :woohoo:
Its been a while! Finally figured out what was wrong. Fuel rail was losing power during crank - long story short I need a new engine wiring harness.
What’s the deal with compatibility? I have a 325is (engine’s out of a '91 convertible) - do I specifically need the wiring harness from a 325is or would this work:
If you know anybody selling one let me know!