[Booztd 3]

Guys

I noticed this issue back when the weather was still fairly cold and figured I would wait until ambient temps got a little warmer to start troubleshooting. Now that it is 'spring' weather I'm going to start digging further...

07' 335i 6spd
JB4
DP's
Both Injectors/HPFP have been replaced at some point.

When I go WOT (and this doesnt happen 100% of the time) the car will throw the check engine light on. The car develops a misfire (and it feels like its missing on more than just one cylinder.) Obviously I pull my foot out of it and resume normal driving, however the misfire continues. Sometimes the CEL will dissapear within 10 seconds, other times it has taken a few minutes - but the CEL will go off and the car will no longer misfire.

Since the CEL does not stay on its difficult for me to hook up and check the codes. I can't remember if the ECM will actually store its logged codes but I figured I would throw a post up before I got a chance to datalog it.

I can assume that its going into limp mode because its detecting a mis-fire, and because the JB4 has auto-clear enabled thats what is clearing the code. Just wondering if it could be fuel injector related..

Thanks!

[rader1]

There is a sticky at the top of the page on misfires. PLEASE READ IT.

[BMWsky]

The codes should still be stored, I'd go ahead and check them.

[jlcolon2001]

Originally Posted by Booztd 3

Guys

I noticed this issue back when the weather was still fairly cold and figured I would wait until ambient temps got a little warmer to start troubleshooting. Now that it is 'spring' weather I'm going to start digging further...

07' 335i 6spd
JB4
DP's
Both Injectors/HPFP have been replaced at some point.

When I go WOT (and this doesnt happen 100% of the time) the car will throw the check engine light on. The car develops a misfire (and it feels like its missing on more than just one cylinder.) Obviously I pull my foot out of it and resume normal driving, however the misfire continues. Sometimes the CEL will dissapear within 10 seconds, other times it has taken a few minutes - but the CEL will go off and the car will no longer misfire.

Since the CEL does not stay on its difficult for me to hook up and check the codes. I can't remember if the ECM will actually store its logged codes but I figured I would throw a post up before I got a chance to datalog it.

I can assume that its going into limp mode because its detecting a mis-fire, and because the JB4 has auto-clear enabled thats what is clearing the code. Just wondering if it could be fuel injector related..

Thanks!

You should disable the JB4 auto-clear feature first, otherwise it will clear the code and you won't be able to read it. What I did when I had the same situation was to drive the car with the JB4 Auto-Clear disable and when I got the misfire and the limp mode I scanned the codes in the dash using the steering wheels controls. I recorded it everything with my smart phone so I could retrieve the codes later. Hope this help.

[imageautodetail]

plugs packs and/or dirty valves

[brakeboost]

Codes will store for up to 5 ignition cycles, how many miles do you have? Sounds like plugs to me.

[Booztd 3]

I finally got around to getting the JB software setup on my other laptop. Noticed there was an interface and a firmware upgrade so I went ahead and performed that before logging.

First Pull resulted in some Cat codes and a misfire code



Second Pull - No Cat codes, but multiple mis-fire codes



The car has 113k miles and I have not put plugs in it since I've owned it (bought at 98k miles) so that will probably be my first step regardless.

[achien]

had your car ever cleaned out the carbon buildup?

if replacing the spark plugs, coils, injectors don't work, you may need to clean out the carbon buildup from the intake valves.

my car experienced similar symptoms as you described and it was resolved with cleaning out the intake valves.

Originally Posted by Booztd 3

Guys

I noticed this issue back when the weather was still fairly cold and figured I would wait until ambient temps got a little warmer to start troubleshooting. Now that it is 'spring' weather I'm going to start digging further...

07' 335i 6spd
JB4
DP's
Both Injectors/HPFP have been replaced at some point.

When I go WOT (and this doesnt happen 100% of the time) the car will throw the check engine light on. The car develops a misfire (and it feels like its missing on more than just one cylinder.) Obviously I pull my foot out of it and resume normal driving, however the misfire continues. Sometimes the CEL will dissapear within 10 seconds, other times it has taken a few minutes - but the CEL will go off and the car will no longer misfire.

Since the CEL does not stay on its difficult for me to hook up and check the codes. I can't remember if the ECM will actually store its logged codes but I figured I would throw a post up before I got a chance to datalog it.

I can assume that its going into limp mode because its detecting a mis-fire, and because the JB4 has auto-clear enabled thats what is clearing the code. Just wondering if it could be fuel injector related..

Thanks!

[Booztd 3]

I've got a majority of the receipts for it however I'm not sure it ever has....

[Booztd 3]

Replaced the plugs tonight and went out & drove the card hard. Didnt' miss a beat.....zero mis-fires