CEL on WOT (high RPM)

[7smurfs]

Copped my first ever CEL today after launching the car and going WOT. When it hit 2nd gear the CEL popped up and car went noticeably limp mode.

I pulled over to the side and turned off the engine. After switching it back on everything seems back to normal however I am hesitant to go WOT again.

Has anyone had a similar issue? Or whether it is simply over boost perhaps and just a one of thing. I fear for my fuel pump....

[1BimmerNut]

Originally Posted by 7smurfs

Copped my first ever CEL today after launching the car and going WOT. When it hit 2nd gear the CEL popped up and car went noticeably limp mode.

I pulled over to the side and turned off the engine. After switching it back on everything seems back to normal however I am hesitant to go WOT again.

Has anyone had a similar issue? Or whether it is simply over boost perhaps and just a one of thing. I fear for my fuel pump....

Had it once when I hit some bumps - the back skipped sideways and got a bit of air CEL came on, engine ran rough, panic set in - re-started and nothing. If you know someone with a scanner/tune you could check it out but ignore unless it happens again

[7smurfs]

No tunes on car so there was no way for me to check what happened.

All speculation atm with the onset panic but will take it to a mech to read the code

[RadiuM]

If it comes up in the small screen on the dash when you do the 'CHECK' command, you can hold down the select button on the stalk for a few seconds and it will show the CC-ID number for that error.

[7smurfs]

Originally Posted by RadiuM

If it comes up in the small screen on the dash when you do the 'CHECK' command, you can hold down the select button on the stalk for a few seconds and it will show the CC-ID number for that error.

Nothing comes up in the check menu. Simply says everything is okay.

Might try later on in the day to replicate the issue.

[BMW86]

Originally Posted by yulook

any tunes on the car?

We really need the code to tell what the issue is otherwise we will be playing a guessing game

It could be anything from sparks, coils or injectors or TMAP sensor issues.

+ 1 Moneel is right.

We need to know the codes to point us in the right direction. Might be worthwhile investing in a piggyback or a P3 gauge as they can read codes.

[7smurfs]

I think this issue gives me the excuse to get the jb4 sooner than initially anticipated !

Edit: did some more WOT runs and couldn't get the car to throw a CEL again. Will take it to active motorwerkes to find out. I was going to do coils/plugs prior to tune anyway!!

[racer_x]

Originally Posted by 7smurfs

I think this issue gives me the excuse to get the jb4 sooner than initially anticipated !

Edit: did some more WOT runs and couldn't get the car to throw a CEL again. Will take it to active motorwerkes to find out. I was going to do coils/plugs prior to tune anyway!!

JB4 will give you more CELs if you're seeing them in stock trim.

You're most probably looking at coil or spark plug related errors. Should be an easy fix once you know what the code is.

[7smurfs]

Originally Posted by racer_x

JB4 will give you more CELs if you're seeing them in stock trim.

You're most probably looking at coil or spark plug related errors. Should be an easy fix once you know what the code is.

I can imagine. I have already softened myself up for preparing for the worst in terms of future repairs -all expected to happen when I had jb4, did not think I'd have my peripherals breaking before then

I hope it's coils/spark plug related although would not be surprised if it was the HPFP or the VANOS solenoid.

Will report back once codes are read!

[7smurfs]

Took it to Active Autowerkes this morning and had Steve read the codes. Came up as misfire on cylinder 5. Was hopeful it was a case of a phantom misfire and off I went.

10mins later on WOT, the CEL light comes on again so I back on the way I am to Active. Steve read the codes once again and it was misfire on cylinder 5. Decided to change the coil on cylinder 5 and hope that it goes away.

No dice. However I now know that CEL appears when the car goes WOT at ~6000rpm.

What should I try next? Spark plugs? The last time the plugs were changed was at 24,500km... car is currently at 46,000km

goddam beemer peripheral reliability and that money sink!

Car is stock...

EDIT: This thread seems to point the issue to the LPFP - I seem to have the exact same symptoms
http://www.e90post.com/forums/showthread.php?t=770611

[Anthony B]

reading a lot of threads & 25,000km seems to be the recommended change of spark plugs for both the n54 & n55. Going to WOT often will see the life on the plugs drop back a little, I was given this method my my mechanic old man for misfires: 1st plugs 2nd ignition coil 3rd scratch head drink a beer

[drjekl]

Originally Posted by 7smurfs

Took it to Active Autowerkes this morning and had Steve read the codes. Came up as misfire on cylinder 5. Was hopeful it was a case of a phantom misfire and off I went.

10mins later on WOT, the CEL light comes on again so I back on the way I am to Active. Steve read the codes once again and it was misfire on cylinder 5. Decided to change the coil on cylinder 5 and hope that it goes away.

No dice. However I now know that CEL appears when the car goes WOT at ~6000rpm.

What should I try next? Spark plugs? The last time the plugs were changed was at 24,500km... car is currently at 46,000km

goddam beemer peripheral reliability and that money sink!

Car is stock...

EDIT: This thread seems to point the issue to the LPFP - I seem to have the exact same symptoms
http://www.e90post.com/forums/showthread.php?t=770611

Change plugs for sure, I had fresh plugs installed by bmw 12 months prior to adding a tune (had about 6k kays use by memory) and after changing coils kept getting misfires...

Pulled the plugs and they looked fine, put a fresh set in and bam it was like driving a new car and no more misfires!

[Kiwi Peter]

If your car has a cylinder miss fire best to replace all the plugs and coils at the same time, doing the one at a time thing is a waist of time.

[Piets94]

Originally Posted by 7smurfs

Took it to Active Autowerkes this morning and had Steve read the codes. Came up as misfire on cylinder 5. Was hopeful it was a case of a phantom misfire and off I went.

10mins later on WOT, the CEL light comes on again so I back on the way I am to Active. Steve read the codes once again and it was misfire on cylinder 5. Decided to change the coil on cylinder 5 and hope that it goes away.

No dice. However I now know that CEL appears when the car goes WOT at ~6000rpm.

What should I try next? Spark plugs? The last time the plugs were changed was at 24,500km... car is currently at 46,000km

goddam beemer peripheral reliability and that money sink!

Car is stock...

EDIT: This thread seems to point the issue to the LPFP - I seem to have the exact same symptoms
http://www.e90post.com/forums/showthread.php?t=770611

Tough one. It could be a few things. Seeing as you're still on the original hpfp, keep that in mind too, especially as it seems to happen at max fueling. As I told you on Saturday my lpfp went soon after my hpfp. But i would have thought you'd get a code for that as well as the misfire. Agree with others that changing one coil or one plug is a waste of time. Whilst you're in there do them all (you'll save $$ in the long run).
Good luck!

[7smurfs]

I agree with you all... the next steps is to do a full replacement of plugs + coils.

Considering the labour costs for 1 coil, might as well save a bit and do them all...

God I hate spending money on maintenance over mods!!

[drjekl]

Originally Posted by 7smurfs

God I hate spending money on maintenance over mods!!

Fresh plugs and coils give you extra power!!!

[7smurfs]

Originally Posted by drjekl

Fresh plugs and coils give you extra power!!!

heh not bang for buck power!

Was dead set on getting a jb4 this weekend... may need to postpone because of this!

EDIT - From my research a high rpm misfire could be the following:

- Check injector seals & decoupling element missing on cylinder 5
- Replace Spark plugs
- Replace Coil packs
- Replace Fuel injectors
- Replace High/low fuel pressure pumps OR LPFP sensor
- Intake valve cleaning (walnut blasting)
- Replace PCV system components
- Reset Adaptations (possibly for tuned cars only)

[drjekl]

Originally Posted by 7smurfs

heh not bang for buck power!

Was dead set on getting a jb4 this weekend... may need to postpone because of this!

EDIT - From my research a high rpm misfire could be the following:

- Check injector seals & decoupling element missing on cylinder 5
- Replace Spark plugs
- Replace Coil packs
- Replace Fuel injectors
- Replace High/low fuel pressure pumps OR LPFP sensor
- Intake valve cleaning (walnut blasting)
- Replace PCV system components
- Reset Adaptations (possibly for tuned cars only)

In 75% of cases a WOT CEL is plugs/coils so definately focus on those 1st.

You'll be pleasantly surprised how much power fresh/plugs will provide along with a smoother driving experience.

[7smurfs]

Originally Posted by drjekl

In 75% of cases a WOT CEL is plugs/coils so definately focus on those 1st.

You'll be pleasantly surprised how much power fresh/plugs will provide along with a smoother driving experience.

I sure hope so! Thanks

BTW if anyone has a spare spark plug socket tool in Melbourne and is willing to lend it to me (or lend me a hand), I'd shout you a carton of beer

[RadiuM]

$17 + $8 shipping: http://www.bikebiz.com.au/products/B...Wall-14mm.html

[7smurfs]

Will look at giving it a go. Have yet to attempt an engine DIY with this car - whereas my previous JDM cars I didn't think twice to just do it