Fuel leak, fixed and now have no spark

[Varinn]

Installed a set of rebuilt m50 injectors into my car yesterday and drove 50+ km to work without issues, went to leave work later in the day and when trying to start the car was just cranking over and over but not catching. Popped the hood and found FPR o-ring on the rail was leaking heavily, I must have fucked up and damaged it while bolting it down. I picked up a new o-ring and installed it and the leak is no longer present but the car still won't start. It has a sound as if it's attempting to fire but never quite grabs. According to the Bentley manual my coil is out of spec, however I called a BMW tech friend of mine and he swears up and down that it's fine and my issue will lie elsewhere. I will check for spark from the coil and cap/rotor condition next as I totally believe my issue is ignition related (fuel on the cap/rotor and shorted maybe?)

Fuel pressure present (but unknown psi)
540 ohms on CPS
12v at ignition coil
0 ohms across primary coil terminals
6000 ohms across secondary terminals
no spark on any leads
coil plug wire 1000ohms resistance
swapped DME's for unmodified stock 173 (mine is chipped) no change
swapped fuel pump relay
swapped main DME relay
checked all fuses in fuse box

Things I have not checked
Fusible link in trunk
cap/rotor condition (about to do this, had to buy an 8mm socket as mine is missing)
injectors actuating (need a helper to crank while I listen with scope)

Is there anything else I can look at? As far as I understand it if the coil has 12v, my issue will be something between the coil and the plugs but my "tech friend" is totally convinced my issue is control related.

[Varinn]

Cap and rotor checked ok, very minimal wear and no moisture inside. I'm still unable to find an answer anywhere if the 0 ohms on primary terminals of the ignition coil is a bad thing, most places on say that if resistance is HIGHER than specified, the coil is bad.

[the_ps]

Do you have a timing light you can put on the coil to distributor lead? You could also test for spark directly from the coil -- it should easily jump any 1/8" or so gap you can make to ground.

[Varinn]

Sadly no, my tool collection is pretty much standard industrial with almost no automotive specific tools. I'll try testing for spark from the coil lead later tonight and replace the CPS (I have a spare from a parts car)

[UserError]

0 ohms means a circuit with no resistance. Mind you, your multi-meter could also use 0 to indicate an open circuit, though that usually shows as O.L. If the primaries are showing 0 ohms resistance, than they're shorted, and you should try again with a known good coil.

[Varinn]

Yup, thanks. I'm very comfortable using my multimeter I just wasn't aware if it was an acceptable reading. Mine shows O/L for no continuity. The Bentley states the spec at 0.5 ohms on the primaries and it says "replace any coil which has higher primary or secondary resistance". I'll try to get a different coil into it and see if it makes any difference, I believe I have a spare one at home (condition unknown however, I'll check it before installing). If the used coil and CPS dont fix it I can investigate further, but I can always buy a new one of whatever ends up fixing it after it starts running again.

[the_ps]

Most digital multimeters are very innacurate below 1 ohm. An analog one is nice to have sometimes.

[Varinn]

I'll look into grabbing one in the future, I don't currently have one though sadly. I've screenshotted the bentley page, and as far as I can see even my reading of 5900ohms on the secondary is enough to say that the coil is bad. I'm trying to get my spare delivered by a friend tonight

[the_ps]

Mine is 5960 and 0.7 ohms.

[Varinn]

Ok, so yesterday I noticed I was no longer getting fuel pressure at the rail, tested and had voltage at the pump. Replaced fuel pump with brand new and now have fuel pressure again but with key on or cranking its just a small drip from return line if disconnected. Swapped coils and rechecked spark at night, spark is present. Injectors dont sound like they're firing when listening with a stethoscope. At this point i dont know what's going on. Plugs on cylinders 1,2,3,4,6 are dry, cylinder 5 plug is wet. Injector plug under intake seems good, full continuity. Im going to try manually grounding the injectors at the ecu next.

[Varinn]

Well I've attempted to run all the injectors by manually grounding the pins at the DME, only cylinder 5 is firing but none of the others. I did notice that on the injector side of c191 there are 7 pins but the female side has only 6 visible connector sleeves. I'm getting the car towed so I can investigate this further at home. I tried swapping back to the original coil and lost spark again, I'm having a hard time figuring out why only some of the injectors are firing and why all of these problems came up at exactly the same time. I am going to try the original fuel pump again and if it's still working I can try and sell it to recover some funds.

[paperplane94]

Pull back the boot of the c191 connector and see if the wires are disconnected/broken off.

After that I would think that the PO messed with the wiring.

[Varinn]

I'm really starting to suspect I'm a victim of the wonderful C191 issues, the pins/sleeves on mine LOOK ok, and there is minimal signs of corrosion but it could be a pulled or loose wire on one half of the connector. If the weather holds tomorrow morning I'm going to rip it apart and check for any loose wires or damage, and voltage at the injectors.

I picked up a new fuel filter as I'm very stumped as to why my brand new fuel pump is running but not delivering any reasonable fuel flow to the rail. If feed hose is hooked up to the rail and I attempt to crank the car it will not start, but when removing the hose I get a spray of fuel from the pressure in the system and fuel will pour from the rail. If I leave the feed line disconnected and crank the engine, I get absolutely nothing out of the hose even when cranking for 20+ seconds. With the feed line connected, but the return line unhooked, I get an occassional drip from the line, no full flow. This has me thinking that my old ass fuel filter is somehow plugged up, and it's time to replace it anyways so it cant hurt to try. I'll check for pump function when I have the line disconnected to replace the filter tomorrow.

[Varinn]

Well I replaced the fuel filter, when I had the hoses disconnected I turned on the key and got zero fuel from the line. Lifted the backseat and checked at the fuel pump, 12v is present in the connector but no movement of the pump, tried moving the connector around and got the same results. Pump is brand new, and after cranking I was getting pressure in the rail but could that be from something else? I'm still not done checking the injector harness, but the no fuel from pump is seeming like a problem...

Edit: pump runs for <1 second during cranking, and indefinitely when manually supplied 12v. Still no flow from lines so I'm going for the long shot that my gauges have suddenly become inaccurate and I don't have the indicated 1/4 tank