Another e36 Crank, No start PLZ help!!

[Static.ty]

So I got this 93 325i about 6 months ago, been replacing little things here and there that its needed. About a week ago I was in the middle of replacing the reverse light switch on top of the trans (manual), I threw the new switch in and fired the car up and put it in reverse and come to find out the switch didn't fix the problem with both of my reverse lights not working.. So I turned the engine off and I tried messing around with the reverse light bulbs, changing them with another bulb and firing the car back up and putting it in reverse to see if the bulbs were the culprit.. Nothing. I repeated this about 3 times and on the last time i went to fire the car up and it ran but then started running more and more poorly then eventually just stalled. Before it stalled i try to push the gas in a little and nothing happened, almost as if it was being starved of fuel.. I tried starting it again and it started then died a few seconds later.

Now the car just cranks and cranks but won't fire up. I've checked and changed out the fuel pump/dme relay and it didn't change anything. I tried jumpering the fuel pump relay terminals and it didn't help either. I removed a spark plug and coil and grounded it on the engine and checked for spark. I seen spark when i cranked the engine. I sprayed a little starting fluid in the intake and it still doesn't start, so that made me think it wasn't getting any spark or not enough spark? If it wasn't getting fuel but just spark, it would have started with starting fluid for at least a second.

So I replaced the crank position sensor as I was leaning towards this being the issue as I've experienced these conditions before and it ended up being the CPS, but still no start! I recently did the spark plugs about 2 month's ago and the car isn't driven. Its just started and ran every once in a while as it's not road ready yet..

Im stumped is there anything im overlooking here? I've been reading on a ton of other forums and I'm not getting anywhere. Not sure why it just crapped out of nowhere!
Any help is greatly appreciated, thanks guys!

[Eric93se]

You may have blown the fuel pump fuse. Never put a larger fuse in.

[Static.ty]

I checked all my fuses and they all are fine. Maybe its just low compression causing the no start.. I'm not sure. Every once in a while it'll sound like it's gonna fire up but just keeps cranking. If it was a fuel issue I think the starting fluid would have let it run for at least a couple seconds.

[enf1945]

you sure the fuse to the Heater control valve is OK ?
you can search to look up the fuse number. I do remember it was brown.

Believe it or not this will not allow your car to start. Happened to me.
If so you need to unplug the wiring to the HCV. It can short inside.

[Static.ty]

Yeah i double checked all fuses for continuity and for resistance and they all check out fine. My car is OBD1 so there can only be so many things to eliminate. I'll double check on the HCV when I get home though. Thanks for the suggestion!

[XnWarden]

Not trying to insult your intelligence, but I've seen this happen before.... Does it have enough gas in it?

Also what kind of fuel pressure are you getting at the fuel rail?

Sent from my VS987 using Tapatalk

[Static.ty]

Yeah no worries I understand! Im still new to these bmw's. The car still has a little over a quarter tank in it. I don't have a valve stem for a fuel pressure regulator. I can smell fuel after trying to start the car. When unplugging the hose that goes to the fuel rail, fuel spits out.

The thought crossed my mind of the cam position sensor being bad, but I'm not sure the cam position sensor would prevent the car from starting, from what I've heard a bad cam sensor will just make it run poorly but it can still start. Is this even true? Could the cam sensor have shorted out and now the DME isn't getting a signal from it to tell it when to spark?? Not sure... I Still have to check the HCV as you stated before.

[Eric93se]

Yes a bad cam sensor can prevent it from starting. The cam sensor will shut off fuel, but since you've sprayed fuel more than once and got nothing then I would guess the sensor is not the issue.

Pulling the fuel hose off is not a test for fuel pressure, your able to pull the hose off then the next step is to put a T and a gauge.

[ed323i]

I second that.. Get a fuel pressure gauge and test it.
If the fuel pressure is too low, or if it's too high, your car won't run. Looking at the symptoms, chances are it's fuel related. So, either fuel pump or fuel pressure regulator gone bad (I once had mine gone bad and it was totally blocked, feeding 7 bar to the fuel rail: complete no start situation which took quite some time to detect the cause).
You could also check if you get a decent spark, by removing one coil, inserting a spare spark plug in it, and grounding the spark plug on the engine block. Be sure not to touch it close to the spark plug as 10kV doesn't feel that nice. Then ask someone to crank it and see if you get nice sparks at even intervals. If that's the case, then you can for 99% rule out the crank position sensor and the DME, and it's a strong indication the either fuel pump of fpr are bad.

[Static.ty]

Yeah I'll have to pick up a pressure reader tomorrow. I already double checked each and every spark plug by using that method earlier, just so I was 100% sure. Its getting good spark. As i pulled and tested each plug the tips came out little wet from gas as well.

I'll have to check into the fuel pressure tomorrow and let you know.

And the HCV is fine enf1945. I checked it out earlier it gets continuity.

[Static.ty]

But if it wasn't getting enough fuel, the starting fluid would have started it for at least a second right?? So it can't be too little fuel... I'd think It'd have to be getting way too much if fuel is the issue.

It sometimes 'puffs' like it's gonna start so maybe im heading in the right direction with the fuel.. Don't know yet, I'll have to find out the fuel pressure before I'm confident.

[doclees]

Did I miss where you said you can or cannot hear the fuel pump running after jumping the relay? If not have you put power directly to the pump?

[Static.ty]

Yeah I can hear it running after jumping the relay. I haven't tried putting power directly to the pump. No codes come up when doing the stomp test to check stored codes. CEL just blinks once then goes solid for a couple seconds. Then blinks once and goes solid.. Over and over again. Im assuming this means no codes stores but if it was no codes it should be 1444. Not sure.

[Static.ty]

So I just tested fuel pressure at the pump using a 300 dollar mac tools gauge im borrowing from a co worker, so it should be pretty accurate lol. When jumping the fuel pump relay and checking the fuel pressure gauge I'm only seeing about 15psi (1 bar) max. From what I've heard it should be about 40-50 psi max. So my fuel pump appears to be real weak..

This doesn't make sense as I've tried spraying a little starting fluid into the air filter twice and the car didn't want to start up for even a second. Well I'll try replacing the fuel pump and go from there.

[Eric93se]

Spraying into the air filter is not even a good idea because the hot film MAFS is right in that area. I've never had to spray any starter fluid into my e36 before but I would have used the brake booster port (and even that is not ideal).

Along with your fuel pump, do the filter and consider the relay.

[doclees]

So low pressure. Fuel pressure regulator is 43 5 ± 1 Psi. Weak fuel pump? Fuel filter? Fuel pressure regulator? Filter the cheapest place to start. Can the pump pressure be tested?

[enf1945]

im sure the fuel filter isnt the problem but a clogged one will shorten the life of the fuel pump.