I'll try with MAF unplugged and good to know about the headlights, thank you.
One troubleshooting guide said I should see the tach move when cranking if the crankshaft position sensor is working, and I definitely do not. Still need to do a quick test for voltage at the coils with key on, as well as voltage at the crankshaft sensor with key on.
If it was an old car I would want to pull a plug wire and check if there is spark,
Is this something you can do ?
Good luck
californiamilleghia said:If it was an old car I would want to pull a plug wire and check if there is spark,
Is this something you can do ?
Good luck
Yep can still be done the same way, only difference is that the plug may be attached to a coil-on-plug rather than a plug wire
No start on ether would mean, a mechanical issue aside, no spark.
if the dme only controls fuel, it's probably not it.
and if it's not firing at all then it is something that controls/affects all of the coils.
the intermittent nature says loose plug or poor fitting connection in a plug.
Try shaking wire harness around while you crank and see if anything changes.
MAF unplugged, no change.
Fuel pressure tested good at fuel rail. Confirmed coil harness has +12 volts in run, confirmed crankps has +12 volts in run.
Robbie (Forum Supporter) said:MAF unplugged, no change.
Fuel pressure tested good at fuel rail. Confirmed coil harness has +12 volts in run, confirmed crankps has +12 volts in run.
sounds like spark .or lack of it ......
if it jumped timing it would still pop if it had spark and fuel ,
anyway to clean the crank sensor ?
Well, in the possibly-worse-case good news possible, I took the key out, flipped it over, and the car started right up no problem and ran great.
Then I was in the odd position of wishing the car would not start when I flipped it back. However, it started again. And again and again, no issues.
But I'm not sure I've changed anything...
So it's intermittent now, Lovely.
The obvious answer is to engine swap, then immediately drive to florida with as little testing as possible. It can't be broken if it isn't in the car anymore.
I vote for bonsai trip that does not involve shutting the car off. I once drove my Runner 20 hours straight without shutting it off due to a starter issue. It would always start after cooling off but I didn't have time for that, a water bath did speed up the process though.
Good luck with this, and remember I'm collecting broken BMWs.
Does that car have speed and reference sensors? If it does and you don't got tach bounce when cranking either the sensors have gone bad or I have found that the wires at the plug to the harnis brake from fatigue.
We use to use the speed and reference sensors from BMWs on Porsche's as they were the exact same part but half the price.
I'm becomming more and more convinced this is some sort of immobilizer issue. From this website (I think the car has BMW EWS 3.3): http://www.unofficialbmw.com/images/BMW_EWS.pdf
The starting sequence of the EWS III (3.3) is as follows:
• The key is inserted into the lock cylinder and switched “ON”. The EWS III (3.3) control module is powered through KL R and sends a 125kHz AM signal to the ring antenna. The AM signal induces voltage in the key coil and powers up the transponder.
• Powered up, the key transponder sends the key identification code to the EWS III (3.3) module. The EWS III (3.3) module verifies the key identification code and checks to see if the key is enabled. If the key is correct and enabled, a password is sent to the transponder over the 125kHz AM signal through the ring antenna.
• When the transponders accepts the password, it releases the changing code which it received from the EWS III (3.3) module during the last start-up operation to the EWS III (3.3) module via the ring antenna.
• The EWS III (3.3) module compares the changing code received from the transponder with the code stored in its memory and if they match the process is allowed to continue. The EWS III (3.3) module looks at the other inputs for correct status (e.g. Code function not active, Transmission in P or N or clutch depressed, engine speed below specified RPM) and energizes the the internal relay to begin starter operation.
New to EWS III (3.3):
• While energizing the internal starter relay, the EWS III (3.3) module calculates a stored code from the “Rolling Code Table” and sends the calculated results to the DME.
• On receipt of the “Rolling Code” from the EWS III (3.3) the DME calculates it’s own stored code and compares its results with the code it received from the EWS III (3.3). If the “Codes” match the drive away protection is released and injection and ignition are enabled and the engine starts. If the “Codes” do NOT match, the DME “rolls forward” to the next code according to the “Rolling Code Table” and makes the same calculations. The DME continues this “forward roll” up to a maximum of 200 times or until a match is found. Failure to find a match will result in the engine cranking but not starting.
• When the ignition is switched off and no engine RPM is present in both the DME and the EWS III (3.3) control module each module will automatically “roll forward” to the next predetermined code based on the “Rolling Code Table”. This new code is used for the next starting sequence.
There is also this GEM:
Workshop Hint: If during diagnosis the key is switched on while the DME or EWS modules are “Disconnected”, the alignment procedure will need to be carried out. The “Alignment” procedure may be carried out an umlimited number of times.
I don't know the alignment procedure yet, but I can certainly see how an engine block short may make the DME or EWS look like they were "disconnected" while the key is in the on position. Maybe I just finally "rolled forward" enough codes to get to one that matched...
It seems from the above that if the key is recognized, the starter will turn. But after the starter is turning there is still a rolling code table process that has to match between the ECU and the Immobilizer module to allow the engine to start.
I read through all that and became increasingly frustrated by each bullet point. All that.. to enable a car to start.
I don't see in that description where it talks to the ECU through anything other then the DME relay. Can the DME relay be bypassed? Like the description makes it sound like the ECU is just waiting for the enine to spin and coils/injectors to have 12V and Grounds. Can you just have the key supply +12V to the DME coils directly and have everything work? But it's probably not that simple?
nocones said:I read through all that and became increasingly frustrated by each bullet point. All that.. to enable a car to start.
I don't see in that description where it talks to the ECU through anything other then the DME relay. Can the DME relay be bypassed? Like the description makes it sound like the ECU is just waiting for the enine to spin and coils/injectors to have 12V and Grounds. Can you just have the key supply +12V to the DME coils directly and have everything work? But it's probably not that simple?
yeah, no one likes a stolen BMW...
To me it looks like there are 4 main communications:
Then starter will engage, but now DME gets involved:
So I think the DME/EWS communication is more than just turning on a relay, probably because people figured out you could start cars in the earlier system via manually applying power to the relay the EWS is supposed to power when the key is good. Notice the DME/EWS stuff is in the "new to EWS 3.3" section.
As long as the DME and the EWS are a matched set (the DME is using the list of codes learned initially from this specific EWS module) and synched, then they should be good from here forward. Unless something un-syncs them, like a B+ cable shorting on the engine block.
In the famous words of Tim the Tool Man Taylor:
"...so I rewired it."
edit: I have an 03 E39, so this is relevant and terrifying enough that I'll just close my eyes and pretend it will all be OK. I wonder what sacrificial offerings I'll have to make for things to stay working.
Glad it started! I would start it on a daily basis to make sure its all good and build up confidence in the car.
My biggest fear would be overnight rain/dew when you bring it. Have to make sure the stuff that has to stay dry, stays dry.
Dude to a plethora of personal reasons (and this looming maybe-fixed-maybe-not immobilizer thing), I have decided to trailer this to the challenge.
The car has been starting faithfully since I got it working again, and I will try to get INPA hooked up to read if there are any immobilizer codes.
Since I'll be trailering, that means I can setup a for sale thread and deliver to people between here and Gainesville on the way home from the challenge! More to come!
Robbie (Forum Supporter) said:Since I'll be trailering, that means I can setup a for sale thread and deliver to people between here and Gainesville on the way home from the challenge! More to come!
Can't say for 100% certain I'll buy it, but shoot me a note as soon as you post the for sale thread. Depending on price, timing, etc...I may be able to give it a good home.
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