HELP: CRANK but no start diagnostic

divinity

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Oct 31, 2013
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I need your help. I just bought my first BMW, it's a 1997 Z3 1.9 automatic with 155k miles. Purchased condition is "NOT RUNNING".

I reviewed the factory service manual, the electrical manual, and searched and searched, but I can't figure out why the car doesn't start.

SYMPTOM: Crank but no start

CHECKED: Fuel pump relay (underdash) GOOD
CHECKED: DME main relay (engine bay, by passenger firewall) GOOD
CHECKED: Brandnew FRESH BATTERY installed GOOD
CHECKED: Fuel pump with jumper (pin 87 and 30) pump does run GOOD
CHECKED: Fuses are good (fuse 13 and 18 engine bay fuse box) GOOD

Note: But I don't hear the pump with relays in place and the key is turned. Also, gas gauge is not working, but I think I did see it showed halftank when I jumped pin 87 and 30.

If both relays are good, why doesn't the fuel pump prime?

Please help!

Thanks,
 
Has the car been standing for a long time divinity?

Mike
 
Have you checked the car for any error codes?
 
old fuel.

blocked injectors.

and finally dodgy pump.

other than that get someone with a laptop to see if its throwing off any codes.

p.s exactly the model I have..you need to join the M44 massive.
 
The car stooped running on previous owner and it had been sitting for about a year.
Throttle body was seized stuck and I fixed that.
There was 0740 code, I'm not exactly sure on the code number but was transmission related.
I cleared all codes, nothing now.
 
If I don't hear the fuel pump runs when the key is turned, then I need to figure that out first before checking further into ignition.
 
Check if you have a spark at the plugs when you crank it over, if no spark the electrics are at fault, take a fuel line off at the engine and see if fuel comes through when you crank it over. if not you know it's the pump or a blockage of some kind. Try pouring fuel in through the throttle body, not too much and see if it fires. Empty the petrol tank as a matter of course and put fresh fuel in it. See the beginning of this post!

Mike
 
You really need to get it on some BMW diagnostic software, if there are error codes present, please post, if there are no codes present, then you need to consider fuel, air and spark.

Fuel - pump, relays, fuses, filter, fuel etc
Air - blockages, splits in induction, throttle body etc.
Spark - plugs, leads, coil packs, fuses, relays etc

But check for error codes first, there are a number of sensors (cam, crank) that will prevent starting, so rule these out.
 
Does the car lock/unlock and is the alarm off as the immobiliser could be on stopping the fuel pump and ignition being turned on. As above you probably need to find a local BMW specialist or a garage that has the Autologic system.

I think most likely are the camshaft and crank sensors because if these aren't giving readings the fuel pump and injectors won't be powered.
 
I only have 1 key for the car, no alarm remote of any kind. I'll research on disabling the alarm or immobiliser.

I'll also buy the BMW factory service manual software from ebay and try to go thru it, step by step and see if that's any better than the Bentley manual i'm using.
 
Which key have you got, the immobiliser is normally a chip in the key, post a photo, it could d be key to a diagnoses! pardon the pun
 
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