Crank but no start

Little.Z3

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(Sorry if I post wrong, first time here!) I have a manual 2001 BMW Z3 2.5L
While driving at night my dashcam and radio turned off and my lights/turn signals slowly dimmed until they were gone too, got home in time and parked the car.
Bought an alternator and replaced it (Lights and radio are turning and staying on now and have no issues with that). The next day I started the car for a second but it sputtered and turned off. I had the battery tested and charged at AutoZone and they say it's a good battery. Got a multimeter, it shows 12.49 and doesn't go below 11 when cranking. Connections are not corroded. Tried connecting a different battery and jumpstarting but they both do the same thing. Can't hear the fuel pump inside the car but can through the gas cap? Tried spraying starter fluid into the intake and it changes nothing. Checked and every spark plug gets spark. RPMs don't even move when trying to crank the car. Got a light up fuse tester from and the fuses seem to be fine... It's making me go crazy.
Video of Z3 cranking
 

t-tony

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Have you had a code reader connected to the car to read any fault codes stored in the ECU. Listening to the video my best guess is the inlet camshaft position sensor has gone bad, but you need to get the codes read.

By the way welcome on here from me near Lincoln, UK. Where are you located please?

Tony.
 

Little.Z3

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Have you had a code reader connected to the car to read any fault codes stored in the ECU. Listening to the video my best guess is the inlet camshaft position sensor has gone bad, but you need to get the codes read.

By the way welcome on here from me near Lincoln, UK. Where are you located please?

Tony.
I'm hoping it is that. I bought a kit that has camshaft sensors and a crankshaft sensor (finally came in today) but I was questioning it since everyone on the Facebook groups are telling me it has to be my battery. I bought the car and it had fuel (too lean) related codes which is why I was thinking it could be a fuel issue and tried spraying starting fluid.
Thank you! I'm from the state of Indiana :) I'm 19 and this is the first car I have ever bought, I absolutely love it and am super proud.
 

t-tony

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You need 3 things to make an internal combustion engine work. You need a spark (which you say you have), you fuel (which you've introduced into the inlet) and you need it be "timed" to occur at the right instance. That would appear to be the only thing which could be wrong. Good luck in getting to the bottom of your problems and when you do enjoy the car.

Tony.
 

NZ00Z3

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Have you fixed the lean fuel trims problems? It's most likely a Vacuum leak. Read the 2 following threads.

If the Rev counter is not showing any movement when you are cranking, then that is a sign that the crank sensor is faulty. It's in a bear of a place to get to. Most people reach up from the bottom and work blind. If you are getting under a jacked up car, always put it on axel stands. Do not work under a car supported by a jack only. They tend to fall off when you wriggle something while under the car. Never works out well. It either hurts a lot or you are dead.
 

Little.Z3

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Have you fixed the lean fuel trims problems? It's most likely a Vacuum leak. Read the 2 following threads.

If the Rev counter is not showing any movement when you are cranking, then that is a sign that the crank sensor is faulty. It's in a bear of a place to get to. Most people reach up from the bottom and work blind. If you are getting under a jacked up car, always put it on axel stands. Do not work under a car supported by a jack only. They tend to fall off when you wriggle something while under the car. Never works out well. It either hurts a lot or you are dead.
I finally got around to replacing the crankshaft sensor but it changed nothing :(
I still have camshaft sensors if the problem could be those. I rechecked the spark plugs and even though they were all originally sparking when I first checked, they aren't anymore. Don't know if it's still the original problem or if it was created because of the orignal problem. Swapped them out with new spark plugs and they still don't spark now. Ignition coils also have no spark on my car but when I swap them to my boyfriends (luckily we both have M54 engines) it has spark. Thinking it could be the wires or possibly a fuse/relay? (I can't find anything on the location of an ignition coil fuse or relay if Z3s have them)
 

Little.Z3

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Have you yet tried a code reader? It's a lot more likely to point you at the real fault than some bunch of people on facebook.
Yes,
PO174 System Too Lean (Bank 2)

P0171 System Too Lean (Bank 1)

P0455 Evaporative Emission System Leak Detected (gross leak/no flow)

P1083 Fuel Control Limit Mixture too Lean (Bank 1 Sensor 1)

P1085 Fuel Control Limit Mixture too Lean (Bank 2 Sensor 1)
 

Althulas

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the Nefyn cat

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Actually in Nefyn. My, that took a while.
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Given a whole bunch of lean codes I'd suspect the inlet hoses, something like these
There's other hoses around, and some spare ports on the inlet manifold that should have blanking plugs that perish over the years
 

t-tony

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Is there any smell of petrol after cranking the engine? I'm beginning to suspect it could be the imobiliser system.

Tony.
 

t-tony

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No spark makes me think the imobilser has kicked in and the key isn't switching it off. Do you have a spare key to try?

Tony.
 
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