Cranks, No Start, No DME Communication - Will strangle bmw engineer(s) for solution

[CptGudentite]

Pre-LCI/Early 07 335i Auto ZF Trans - Slightly NOT stock

Car acts totally normal, lights come on, everything is good... click ignition button on, pump primes and never goes off, water pump can be heard turn on, clicking in engine bay just like normal when ON is pressed, car cranks strong... no start, no fuel smell. Cant communicate with DME via known good MHD and OBD2 Blutooth w/Torque

• new built motor installed after car sat for 1 year no battery
• no start
• no dme communication
• no fuel injecting into engine
• fuel pump constantly priming/circulating gas when ignition is on
• jb4 completely removed
• new fuel pump and fuel pressure regulator
• checked all glovebox & DME box fuses multiple times
• swapped DME for backup 2nd cloned DME
• checked/bypassed blue dme relay and 30g fuse box relay
• checked all engine sensors are installed and proper plugs connected to engine
• checked main ground strap & power wire to/from starter & alternator
• battery voltage ~13 when off of charger but charger is left on charger during all work
• disconnected IBS sensors to battery

Mods

• Engine - Forged Rods/Pistons/Ported Heads
• Hybrid Stage 2+ Turbos
• Index 12 Injectors
• NEW Stage 2+ Fuel Pump
• Charge Pipe w/Tial BOV
• 3.5 Bar MAP
• Big Aftermarket Intercooler
• Relocated Inlet/Outles
• Downpipes
• Borla Sport Exhaust
• Catch Can
• PCV Valve
• JB4 BEF w/MHD (currently removed)

Currently working on the car, this is my TLDR version... will add full version later, hoping for some ideas to try asap. Ive had similar issues before with this car but always figure it out eventually. I could strangle some german bmw engineers right about now though.

Any help is greatly appreciated, I dont give up easy... it WILL start just a matter of time. :burnrubber:

Thanks!

 

[CptGudentite]

Was the key programed to the casino? I think all the things have to match.

As far as I know it was the matching key for the MSD81, CAS and driver door lock. It should have worked... the only thing I can think of is the fact my car isnt comfort access and donor vehicle was. I am trying to hunt down that key for the MSD81 right now... I have the CAS and driver door lock for it... cant find the key atm.

 

[doublespaces]

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[antonio186]

I know this issue was solved for the OP. And it turned it to be a faulty ground. I have a very similar issue on my early 06 E60. The engine cranks strong, I get fuel to the fuel rail, I checked all fuses in the trunk and in the glove box. I haven't checked the relay for the DME yet, will plan to do that this weekend. When I hook up my laptop to the OBD2 port it shows no communication with the DME. This all happened after a long cold winter last year and the battery went flat. After charging and recovering the battery the 1st issue that popped up is the ELV was acting up. Somehow that got out of sync with the CAS module and I eventually got it start responding again. But it still wouldn't start. Anyway long story short I have had the battery out of the car now for a few months and I decided to start looking into the issue again. I have checked all the ground straps I could see and checked continuity between both sides of each strap. I am wondering if there is something simple I'm over looking. Any help would be appreciated. Thanks

 

[Stevenbmw525i]

WE HAVE IGNITION! and im a fool... but I figured it out.

Damn ground on the strut tower passenger side was hidden between the heat shield and strut tower... under the relocated inlet pipe. Figured it was something stupid and simple right in front of my face but I never saw it.

I setup INPA, started followed the service plan... every step, checking the circuit line... each connector, fuse, relay... and then finally grounds... soon as I clicked the picture showing that ground it clicked in my head.

So boys and girls dont be like me... remember those pesky grounds that are hiding from you.


Thanks to everyone who helped and I hope we all got a good laugh out of this.

Ill update yall on how the new motors does!

Im having same issue can someone please tell me were all my grounds are on a 2003 525i i have done a engine ,and transmission swap from a 2002 525i ,and im getting no crank no start its been 3 months please help

 

[brock]

WE HAVE IGNITION! and im a fool... but I figured it out.

Damn ground on the strut tower passenger side was hidden between the heat shield and strut tower... under the relocated inlet pipe. Figured it was something stupid and simple right in front of my face but I never saw it.

I setup INPA, started followed the service plan... every step, checking the circuit line... each connector, fuse, relay... and then finally grounds... soon as I clicked the picture showing that ground it clicked in my head.

So boys and girls dont be like me... remember those pesky grounds that are hiding from you.


Thanks to everyone who helped and I hope we all got a good laugh out of this.

Ill update yall on how the new motors does!

HI from Spain! im having the exact same problem in my n54 2009 i check everything and i cant solve the problem.

Can you explain a little more how do you find the problem? sorry but i dont understand complete in english

i need yo check the ground floor under the strut tower and find what? i recently change downpipes and turbos so maybe the are a problem in that zone...

Thanks for the help man!

 

[NoQuarter]

Something to remember with these ground straps....

They have to carry a lot of current. They may be deteriorated enough to not permit enough current to pass for some loads but still may allow some things to turn on and pass a continuity test.

 

[brock]

Something to remember with these ground straps....

They have to carry a lot of current. They may be deteriorated enough to not permit enough current to pass for some loads but still may allow some things to turn on and pass a continuity test.

interesting! do you have some photo os that straps? are near to the passanger ground?

i have current in 3 of 4 plugs of the DME but one of the canbus dont have ther correct current of energy (motor canbus) and the motor shakes and dont start.



thanks for the advise