Engine Warning Light N54 135i

Sendhur

Member
Morning Fanatics

After pushing my car hard a month ago my engine warning light came on and power was cut, after the car spent a few days at BMW (it is still under motor plan) they could find nothing wrong after they changed the spark plugs with the service the light did not come on again, yesterday after pushing my car hard the engine light came on again and power cut again I will now have to send it to BMW again. I do know from reading on the forum the X35 models engine warning light comes on quite often. Has anyone experienced the same issue, as it seems to only come on when the car is pushed hard.

Your input would be appreciated.:thumbs:

Thanks Fanatics :thumbs:
 

Twinz

Forum - Support
Staff member
Do you have a way of reading the codes that were thrown? Thats a good starting point.
 

bybyM3

Member
+1 on codes.

There could be a variety of explanations, however what i discovered on my N54 was a fueling issue. When my trims are at 0, meaning no fuel in the engine i run a light.

This is due to the fuel pump not been able to keep a constitant pressure. High up in the rev range say 5500+ my fuel pump drops to below 40 psi and based on the engine requirements you need to be in the 70psi mark. This drop in pressure will definately casue a light, but once the power drops and pressure increases you will notice that the light will disappear.
 

Sendhur

Member
Thanks for the feedback Gents, much appreciated I will get the codes read this afternoon and will take it from there.

@bybyM3 would a upgraded fuel pump be a solution on that? will BMW cover it under motor plan? or will I have to put up with this happening?

Thanks once again - I will provide more information once I get the codes read
 

boost3d

Honorary ///Member
What engine do u have in your x35.

Is it N54 or N55?

The N54 has a known problem with hpfp and the injectors but it has to be picked up by BMW on its machine for them to replace them . They won't replace it if they don't find a problem (idiots)
 

LukeS2K

New member
Hmmmm, Ive had similar issue with mine. When I restart the car though the warning light disappears. Also only occurs when pushing the car a little.

I thought perhaps it relates to an increase in your coolant temps so the engine just goes into limp mode to protect your Turbo's and engine etc.

Mine is a N54 335i.

Come to think of it my fuel was very low when it came on, so could definately relate to a low fuel pressure.

Note to one self, dont boost hard when your fuel is low :thumbs:

My mate has that plug in device which reads the codes onto your iphone.Its a phone app. Next time it comes on Ill have to drive straight to him to check it out. We tried after the fact but there was no record of it.
 

Sendhur

Member
@German_Spec it is a 135i N54 Manual transmission, thanks for feedback, So lets see what BMW says

@LukeS2K please check with your buddy where I can get this plug in device from sounds like it will help me and is convienient to read from Iphone
 
S

SP33DYV

Guest
Sendhur, you still under motorplan? If you are drive the car hard and when you get the error, straight to the dealership without switching it off and let them have a look. Like stated above, it is probably the HPFP or injectors. Hope you get it sorted. :thumbs:
 

bybyM3

Member
the fuel pump can be replaced, but to prove its faulty is very difficult. What octane you running

if you can log your car than i will be able to tell you if it is the fuel pump or not. If the pressure drops during high RPMs than it could be a possibbility.


SP33DYV said:
Sendhur, you still under motorplan? If you are drive the car hard and when you get the error, straight to the dealership without switching it off and let them have a look. Like stated above, it is probably the HPFP or injectors. Hope you get it sorted. :thumbs:

If it is fueling relalted the code will disappear, than by the time you get to the dealer it will not be there.

Another test you can you to determine if it is the pump is run the tank to a couple of liters and do WOT. Check if the light comes on, if it does than you most probably have an issue. I am basing this reply on the fact that you dont have access to log your car.

If you can log your car tahn send me the log but include fuel pressure in your display.

:thumbs:
 

Sendhur

Member
@SP33DYV yep I am still under motor plan bud I will be driving it hard and taking it straight there - thanks bud

@bybyM3 running normal fuel (no octane booster) car is also completely stock, Once I run the logs tonight I will let you know what readings i get - Thanks bud
 

Philip Foglar

///Member
SP33DYV said:
Sendhur, you still under motorplan? If you are drive the car hard and when you get the error, straight to the dealership without switching it off and let them have a look. Like stated above, it is probably the HPFP or injectors. Hope you get it sorted. :thumbs:

+1!

Don't muck about with this and the agents - get the car to go into this limp mode and straight to the dealer!! HPFP and also injectors are usually the culprit - ask them to check the serial numbers of the injectors, apparently they have some sort of list of faulty batches and maybe your car has them or just a few of the affected ones.
 

Sendhur

Member
Philip Foglar said:
SP33DYV said:
Sendhur, you still under motorplan? If you are drive the car hard and when you get the error, straight to the dealership without switching it off and let them have a look. Like stated above, it is probably the HPFP or injectors. Hope you get it sorted. :thumbs:

+1!

Don't muck about with this and the agents - get the car to go into this limp mode and straight to the dealer!! HPFP and also injectors are usually the culprit - ask them to check the serial numbers of the injectors, apparently they have some sort of list of faulty batches and maybe your car has them or just a few of the affected ones.

Thanks Philip will do :thumbs:
 

LukeS2K

New member
Sendhur said:
@German_Spec it is a 135i N54 Manual transmission, thanks for feedback, So lets see what BMW says

@LukeS2K please check with your buddy where I can get this plug in device from sounds like it will help me and is convienient to read from Iphone

Will do. Going past him today. Its an amazing little thing. I couldnt believe it.lol
 

Sendhur

Member
@LukeS2K thanks bud much appreciated

Just a update to all those that have helped with advice, the car is going into BMW this afternoon I hope they sort out this issue - I have also specifically asked them to check the HPFP and Injectors - I will keep you posted on what happens

Thanks once again Fanatics :thumbs:
 

LukeS2K

New member
If anyone is interested in that plug in jobby that reads all your engine data and error codes then you can give my buddy a call. Andre 082 459 7411. Its about R450 bucks.Then you just download the app to your phone. The app is called Torque. Took him about 30 seconds and he had all my data, coolant temps, intake temps, revs,fuel consump, etc etc and most importantly a log of all error codes. Pretty neat.
 

Sarishen

New member
Hope you get sorted soon Sen... The loaned 320d will have keep you going till your N54 monster is back :=):
 

Sendhur

Member
Update: Got a call from BMW according to them the turbos are the issue the mechanic is still investigating and it might need to be balanced or replaced,

Hectic Lucky I have Motor Plan

what causes this to happen?
 
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