Z4 Masterminds wanted: Engine cranks but will not start- tried everything! Help!

[ncmish]

SOLVED!!!!

(This is my first post so apologize if this is in the wrong place, or if this problem has been covered -- I have searched and searched with no luck – feel free to move)

Details: 2008 e85 Z4 with N52 (MSV70). Has 113,000 miles.

Model is a 3.0i, but did a 3-stage conversion with Bimmerlabs 3.0si tune. RSA Delete and Tune with 3 stage manifold were done two weeks ago – once complete car drove just fine (Better!) until this weekend.

Problem: Engine cranks but will not start. The problem began a couple days ago when it didn't start (still cranked), but then start after waiting 10 minutes. Happened again Sunday, engine wouldn’t start (cranks) but then randomly started one time. Over the past 24 hours will not start (still cranks).

Ruled out:

• Flooded: I pulled the plugs from the engine – dry – no excess gas
• Spark plug/coils: replaced three months ago
• Immobilizer: Since the starter engaged I’m assuming no EWS or immobilizer issue – also no codes and INPA verifies the key. I also have two additional keys I tried with the same issue (yes, I have three coded keys)
• Battery: I have a tender hooked to the battery during the entire process and the battery is only 3 months old
• Fuel: No codes for fuel – and I can hear the fuel pump prime (unless I am missing something)
• Relays: I replaced the two purple relays I believe might be for the DCE (not entirely sure). They were purple and under the glove box against the firewall. And just to point out – there are no relays in the ECU box under the hood – just wire harnesses and the actual ECU (I think they changed this in 2006 on Z4s)
• FUSES: I checked all DCE related fuses and the ones next to the DCE under the hood – any others I should check?

CODES Thrown: All ECU Related:

• 2A80 Intake VANOS, activation
• 2A85 Exhaust VANOS, activation
• 2A19 Tank-venting valve, activation
• 2AA8 Variable intake system, servomotor: activation
• 2AA9 Variable intake system, servomotor 2: activation
• 2EF5 Map thermostat, activation
• 2EA1 Oil condition sensor, communication
• 2E85 BSD, message; electric coolant pump: missing

If I clear them they all come right back.

Honestly I am really nervous if this is coding related -- Im a noob and flashing the Bimmerlabs tune and poking around in INPA is my skill set is at this point.

Help?!

__________________________________________________ ______________

SOLVED: The issue was the DME Relay was broken. The problem is the Z4 2006 - 2008 (also the X3) have an IMV that houses the DME Relay on a circuit board. Its very unusual for BMW and found OUTSIDE of the ECU/DME engine compartment.

Here is a picture of the DME Relay, ECU fuse box with integrated circuit board. Picked one up for $40 on eBay and car fired right up!

[Michael9218]

Ironically, I’m going through the same thing at the moment with my M Coupe track car. After much analysis with Randy at Epic, we have come to the conclusion that the ecu is faulty and/or the immobilizer is somehow active behind the scenes. Also confirmed by a gentleman I spoke to at Precision ECU. I am awaiting a reflashed replacement ecu.

[ncmish]

Originally Posted by Michael9218

Ironically, I’m going through the same thing at the moment with my M Coupe track car. After much analysis with Randy at Epic, we have come to the conclusion that the ecu is faulty and/or the immobilizer is somehow active behind the scenes. Also confirmed by a gentleman I spoke to at Precision ECU. I am awaiting a reflashed replacement ecu.

Just out of curiosity -- did you experience the same codes? I would have thought it was the immobilizer as well -- but im not getting any codes and can see it active and reading my keys on INPA.

Also -- how sweet would it be to have an M Coupe track car!

[M-Cast]

Did you check the throttle actuator? Check to make sure you are getting power there at both end points.

[ncmish]

Originally Posted by M-Cast

Did you check the throttle actuator? Check to make sure you are getting power there at both end points.

Would that cause all the codes to be thrown? Ill look into it.

[M-Cast]

Originally Posted by ncmish

Would that cause all the codes to be thrown? Ill look into it.

If the car is turning over, but not starting especially after doing the upgrades you just have done there could be something preventing fuel to pass and fire the engine. I ran into a similar problem when I installed Dinan throttle bodies. Pull the air box off and check to see if your throttle bodies are getting power. There is an auto turn off function that cuts power to the throttle body. Either way take a meter and test to make sure you are getting power and then go from there.

[ncmish]

SOLVED: The issue was the DME Relay was broken. The problem is the Z4 2006 - 2008 (also the X3) have an IMV that houses the DME Relay on a circuit board. Its very unusual for BMW and found OUTSIDE of the ECU/DME engine compartment.

Here is a picture of the DME Relay, ECU fuse box with integrated circuit board. Picked one up for $40 on eBay and car fired right up!

[3002 tii]

Originally Posted by ncmish

SOLVED: The issue was the DME Relay was broken. The problem is the Z4 2006 - 2008 (also the X3) have an IMV that houses the DME Relay on a circuit board. Its very unusual for BMW and found OUTSIDE of the ECU/DME engine compartment.

Here is a picture of the DME Relay, ECU fuse box with integrated circuit board. Picked one up for $40 on eBay and car fired right up!

Attachment 2339720

Congrats on the fix... how’d you ultimately diagnosis it?

[saintex]

And I'm curious....where is this strange creature (aka relay fuse box ) located ?