Subject: You have an E36. This is E46. HOWEVER. Author: Shayne (moderator) : member since July, 2005 : 5386 posts Posted on: 2009-10-30 12:00:12

You can't have fuel and spark if the engine won't start UNLESS you have water in the fuel. Add 1 litre of Methyl Hydrate to the fuel tank and let it sit for about an hour. Now you need to cycle the fuel pump. Pull the fuel pump relay and jumper the primary side and let it run for a couple of minutes.
If this does not work the CPU is probably not the issue unless you have EWS then it needs to be programmed to your key... however the car should not crank over.
Here's what happens when you turn over the ignition to the start position:
The fuel pump relay engages and primes for two seconds then turns off. The engine spins one half revolution and the DME (CPU) picks up the signal from the CPS (Camshaft Position Sensor) to find cam timing. As the engine makes its full revolution the DME figures out crankshaft position/timing from the CPS (Crankshaft Position Sensor) and releases the ignition, the fuel pump relay so the fuel pump engages, the heater for the O2 sensor engages, and the fuel injectors are released. The engine now starts.
If one or both of the CPS's are weak or the gap is set incorrectly the engine may take an extra revolution to start. If they have failed the engine has no idea where the cam and/or crankshaft are and will not release the fuel pump or ignition.
Many believe that if the fuel pump relay does not engage this is a fault of that circuit but I have never experienced this.
Failure of the fuel pump relay is only due to two things.
Poor or no CPS signal. No power from/to the Main Relay.
1. So first you are looking for power TO the DME via the main relay.
The main relay is silver or white depending on manufacturer. With the ignition in the 'Run' position you should have power to the Main Relay on both the primary and secondary side. With a meter just probe all of the slots and two should have 12 volts. If they don't then you need to find the fuse supplying the main relay.
If you do have 12 volts to two pins then plug the main relay in with the ignition in the 'run' position. It should click. If it does not replace it.
Now you need to look to the CPS's. You can test them but replacement is advisable.
Number 17 here is the Cam Position Sensor
Part 18 here is your Crank Position Sensor
Only purchase OEM. Aftermarket sensors are not dependable. For best prices try AutohausAZ, Pelican Parts, or Bavauto.
My concern is what exactly got wet?

Shayne
525iTA
330iA



I don't know the same things that you don't know.

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  • You have an E36. This is E46. HOWEVER. (url) - Shayne 2009-10-30 12:00:12 (50 views)