[borisivan]

Hi,

My 2010 335 E90 MT is out of warranty (~60k miles) and is having the occasional hitch/misfire, usually only seen when in 4th/5th/6th -- usually as soon as I engage the throttle (i.e. within the first second or so I'll sometimes feel one hitch/misfire, and then it's usually misfire-free) The problem first occurred after a spark plug change -- I think it's the original injectors.

Occasionally at idle, there is an occasional hitch/misfire.

Going in for service next week --- is there any chance this is considered part of the powertrain warranty, or covered under any of the class action stuff?

I'm low on $$ and am not looking forward to having them spend hours and hours trying to diagnose it at my expense. Figured it was worth asking.

Regardless -- I've been away from the boards for a while --- any likely culprits? I think it's the original set of injectors, and the problem only developed over the past 6 months or so, so I'm guessing it's not an injector coding issue, correct? Anything else worth looking at?

Thanks in advance for any advice!!

[Beemw335]

Coils injectors fuel pump or even bad carbon buildup.
Best thing is to scan for codes and see whats going on.

[GeorgiaTech335coupe]

My guess is injector. You really need to figure out which cylinder it is. Do you have a way to scan the codes?

[JamesM3M5]

Mine is a 7/2006 build before the injector recall, but I have a feeling that my injectors are to blame for the occasional stumble/bump feeling when cruising low throttle below 2000RPM and idle. Going to have my extended warranty cover replacing all 6. I've already cleaned the carbon and replaced the injectors. It's not consistent with power delivery, just light throttle cruising below 2000RPM. Really annoying!!

[borisivan]

Originally Posted by GeorgiaTech335coupe

My guess is injector. You really need to figure out which cylinder it is. Do you have a way to scan the codes?

re: scanning codes -- I have the BT cable and application, I'll look for any codes / shadow codes, but I don't recall seeing any the last time I looked. The check engine also never comes on for this.

Were you referring to those types of codes, or were you referring to the injector programming? I'm just coming up to speed on that thread now -- is that something that I can read with the BT tool too, or does that require a different cable/application?

[JamesM3M5]

Originally Posted by borisivan

re: scanning codes -- I have the BT cable and application, I'll look for any codes / shadow codes, but I don't recall seeing any the last time I looked. The check engine also never comes on for this.

Were you referring to those types of codes, or were you referring to the injector programming? I'm just coming up to speed on that thread now -- is that something that I can read with the BT tool too, or does that require a different cable/application?

BT tool does not support injector coding, yet. You need an INPA cable and software. There are threads here in the N54 forum on what to get and how to set it up.

If you want to tackle it yourself, it is rather straightforward. It will save you a lot of $$ since the dealer or independent shop will have to charge quite a bit. Retail is $134 each injector, $107 if you get them from getbmwparts.com. Don't forget to buy and install new "decoupler elements" with each injector, $8.17 retail / $6.54 each.

My bet is injectors, but it's best to check for codes, make sure your plugs are in good shape or replace them if they're more than 25k miles old, and make sure there isn't a lot of carbon build-up in the intake. Do the easier/cheaper stuff first, of course.

[borisivan]

Thx for the advice!