Any help appreciated as scratching my head. Run codes and came back cylinder 1 misfire, tried a better code reader and discovered that there is no spark to cylinder 1. So cylinder 1 not firing at all. Things I’ve done

changed spark plugs

changed leeds

changed to a brand new coil pack

still not firing

 

where should I look next?

Morning Cad 

Check very carefully the Loom from the DME to the coil pack for any sign of wear chaffing cracks or breaks also check the Injector loom the same would be where I would start

Good Luck

Dave

Ok so checked wires to ecu. I have resistance from ecu to coil pack. Took number 1 leed out and put in to number 4. Put number 4 into 1. Number then wouldn’t fire. Swapped the leed out completely for one that I know works and still won’t fire. Would this be an ecu issue? And can I just put another ecu in (plug and play)

Morning Carl

A diagnostic read is the real answer to give a better feel for what is happening. If you like to be able to fix stuff yourself, it is worth investing in a Copy of BMW 1.4.0 it will give Dealer level access and all faults are explained in English 

Check www.realoem.com put the last 7 digits of your Vin into the search box it will call up your model. Then search for what you need by way of part numbers

Changing the ECU isn't just plug and play I believe you need the DME EWS driver's door lock and keys and then some programming to 

You could talk to repairers like ECU Testing or BBA Reman if you can get your tested and repaired you shouldn't need to change the other stuff.

Good Luck

Dave

Cheers Dave

had a mechanic friend of mine plug his reader in. All it said was cylinder 1 misfire. Even did a read with engine running and the same. It’s almost like the ecu is telling it not to fire for some reason. I think I have eliminated everything else?

Morning Carl

Then I would definitely talk to ECU Testing, BBA Reman I know they give a very fast turn around and normally if they can't repair it then no charge. I have used both companies for Control unit repairs on Volvo Mercedes and Ford over the years and found either to be quick and efficient.

If they can repair your ECU the advantage, is you can plug it back in without any re-programming issues. You have checked the Injector at No1 also a compression check.

I had the DME fail on my X5 E53 4.6is it couldn't be repaired, I brought a DME with matching EWS Drivers door lock and Ignition barrel and Keys fitted them and re-programmed the DME to my chassis (not necessary but keeps things tidy in my engineer's head) 

Dave

Compression test was one of the very first things I did. All cylinders good. Gonna send ecu off for testing. What would cause an ecu to fail? And how can I prevent it in the future?

Hi Carl

I have seen a failed DME where a faulty thermostat sensor allowed coolant to wick up the loom and caused serious damage to the printed circuit board. My own DME failed due to corrosion at the pins 2 being so bad new ones couldn't be soldered in. You could try some electrical contact cleaner on the plug and the pins.

If you get yourself an old Win 7/8 laptop and a copy of BMW 1.4.0 you will get far more information than from your mate's code reader (Unless he has inpa/ISTA or similar) You can not only see faults it will explain what it is, you can see live data which will indicate the function that is failed/failing. You can program good used parts to your chassis (Dealers will tell you it can't be done) making sure everything works correctly.

Fingers crossed the DME can be fixed and sorts your problem

Dave