[Wahish335i]

hello, I have a 2010 bmw 335i xdrive with a no start problem. I have spark, fuel and compression. here's a lil more info on the car before I get into it

I replaced the head gasket
changed the crank hub and timing chain
Upgrade to "eBay" 19t turbos

my mods are:
PI 750cc
Fuel it stage 2 LPFP for full e85
19t turbos
inlets and outlets
FBO
mhd stage 2 plus
xhp trans tune

So it started fine the first couple of times now all it does is crank and makes a really really loud bang. before people come at bc of the head gasket I took the head off bc I bent a few valves and the the intake already needed to be walnut blasted to it was a two in one and bc I was already in there I upgrade the crank hub and changed the chain bc why not. I currently don't have a tune for the turbos but I don't think it wouldn't start and make loud popping noise. what's strange to me is that im throwing no codes at all and I used multiple scan tools and still no codes. at first it was misfiring in cylinder 1,2,4 and but would run, I changed the injectors had them coded and still nothing here's a checklist of what I did.

Camshaft and crankshaft sensors are OEM new
it has 80 psi before the HPFP and 2400psi at the crank
changed the knock sensors
check timing and its good
timing chain tensioner is new and torqued to spec
brand new spark plugs, coils, injectors
the cylinders are all in good shape
rod bearings have been replaced I replaced everything in the motor besides the pistons

this car is killing me and a pain in my a*s
im open to options and new a fresh set of eyes on and all my friends are not n54 fanatics like me and most mechanic shops near me don't even know where to begin
I know I stated my problems but to simplify it. IT DOES NOT START BUT CRANKS AND IM GETTING NO CODES
Thanks in advance and like I said im open to anything

[C4maro]

Try unhooking the battery and hooking it back up.

[Tyc0]

If you know you have fuel and you know it's getting air, have you checked for spark?

[C4maro]

Originally Posted by Tyc0

If you know you have fuel and you know it's getting air, have you checked for spark?

"hello, I have a 2010 bmw 335i xdrive with a no start problem. I have spark, fuel and compression. here's a lil more info on the car before I get into it"

[Tyc0]

If you are sure you have all of those things then it must be some finicky bmw thing and I am unsure where to go from there.

[IllSic_Design]

damn seems like you check all the mechanical things. I was going to say check the timing again because of the pop/bang when trying to start sounds like its out of time, but nvm. I'm thinking its got to be something electrical/elec controlled. Sorry I can't really be of use, I'll be thinking about this while at work and let you know if I think of anything

[ab987]

Can you upload a log of a failed start?

[Saif2018]

Originally Posted by Wahish335i

hello, I have a 2010 bmw 335i xdrive with a no start problem. I have spark, fuel and compression. here's a lil more info on the car before I get into it

I replaced the head gasket
changed the crank hub and timing chain
Upgrade to "eBay" 19t turbos

my mods are:
PI 750cc
Fuel it stage 2 LPFP for full e85
19t turbos
inlets and outlets
FBO
mhd stage 2 plus
xhp trans tune

So it started fine the first couple of times now all it does is crank and makes a really really loud bang. before people come at bc of the head gasket I took the head off bc I bent a few valves and the the intake already needed to be walnut blasted to it was a two in one and bc I was already in there I upgrade the crank hub and changed the chain bc why not. I currently don't have a tune for the turbos but I don't think it wouldn't start and make loud popping noise. what's strange to me is that im throwing no codes at all and I used multiple scan tools and still no codes. at first it was misfiring in cylinder 1,2,4 and but would run, I changed the injectors had them coded and still nothing here's a checklist of what I did.

Camshaft and crankshaft sensors are OEM new
it has 80 psi before the HPFP and 2400psi at the crank
changed the knock sensors
check timing and its good
timing chain tensioner is new and torqued to spec
brand new spark plugs, coils, injectors
the cylinders are all in good shape
rod bearings have been replaced I replaced everything in the motor besides the pistons

this car is killing me and a pain in my a*s
im open to options and new a fresh set of eyes on and all my friends are not n54 fanatics like me and most mechanic shops near me don't even know where to begin
I know I stated my problems but to simplify it. IT DOES NOT START BUT CRANKS AND IM GETTING NO CODES
Thanks in advance and like I said im open to anything

Going of a tangent here, if your battery is fine, What about the starter motor itself?

[Supahone]

The backfire is a clue. I would guess your timing is off or your timing sensor / cam sensor are bad or faulty. They can burn out after too many cranks or having sludge on them from poor oil changes. Make sure they are connected properly, not shorted or torqued down properly. Hate electrical gremlins!