This just happened....any ideas?

[docpanama]

Hey y'all-
I was driving to work just now, and while stopped at a light, the engine started running rough, out of balance, shuddering at idle. CEL came on. Seems to me a coil went out. Made it to work, turned car off, and just out of curiosity, re-started car, and it ran smooth as silk with no CEL.

anyone else ever have this happen? SHould I bring it in or wait to see if it happens again? Full disclosure: I just replaced all the coils with Bosch coils. One of the ones they sent me was bad, so i have 5 new Bosch and 1 Eldor of indeterminate age (although the car only has 28000 miles and the Eldor isn't factory so....

Matt

[02Pilot]

Don't guess. Scan the car with a proper BMW-specific code reader (not generic OBD2, which is misleading and nearly useless), or have it scanned if you don't have the tool, and report the codes.

[docpanama]

Originally Posted by 02Pilot

Don't guess. Scan the car with a proper BMW-specific code reader (not generic OBD2, which is misleading and nearly useless), or have it scanned if you don't have the tool, and report the codes.

Yeah, I suppose you're right about not trying to guess at it. I'll call the shop.

[Dackelone]

Scan for codes first. You don't want to Scotty Kimore your car. lol

Since you JUST replaced five of your six coils... I would start by double checking your work first. It's easy to not get those connectors fully onto the coil packs. Open each one up and reinstall the electrical connector. Also push down on all the coil packs to make sure they are fully seated.

[JimD]

The OBD codes are primarily governmentally mandated so I see no basis for comments about brand specific code readers. I have two generic ones that read and clear the codes on my BMW and my other cars. Different brands do create their own codes, in addition to the ones they have to have, but you can read them with a generic reader (and clear them too) but may have to google them to get a description. I usually goggle the codes even with the reader provides a description because I get more information that way. I guess it is possible I will get a code that I cannot sort out this way but it hasn't happened yet.

[02Pilot]

Originally Posted by JimD

The OBD codes are primarily governmentally mandated so I see no basis for comments about brand specific code readers. I have two generic ones that read and clear the codes on my BMW and my other cars. Different brands do create their own codes, in addition to the ones they have to have, but you can read them with a generic reader (and clear them too) but may have to google them to get a description. I usually goggle the codes even with the reader provides a description because I get more information that way. I guess it is possible I will get a code that I cannot sort out this way but it hasn't happened yet.

Ask any BMW tech and you'll hear the same story: OBD2 codes are misleading to useless. While they are supposed to be universal, the fact is that there are too many variables and changes in technology since they were introduced in 1995 to make that even remotely possible. Further, they are only concerned with emissions-related equipment, so there are countless BMW codes that simply cannot be viewed with a generic reader.

I've stuck my reader on cars with no OBD2 codes and no CEL and found multiple active codes (and more stored), and on cars with a CEL lit the difference between specific and generic readings can be surprising.

Whenever you have a non-emissions-related problem you will quickly discover how limited OBD2 readers are on these cars.

[JimD]

I accept that I may have a code some day that my readers will not detect. But it has not happened yet on any of my cars. If I get a check engine light, I have been able to see the code and clear it with what I have. If that ever changes, I may think about a different reader. But I kind of doubt it will change.

[02Pilot]

Originally Posted by JimD

I accept that I may have a code some day that my readers will not detect. But it has not happened yet on any of my cars. If I get a check engine light, I have been able to see the code and clear it with what I have. If that ever changes, I may think about a different reader. But I kind of doubt it will change.

You have not had a code that you know about. There may well be stored codes that are not emissions-related. There are a lot of body modules that report codes that are totally inaccessible to OBD2 readers and which do not trigger a CEL.

I once put a reader on an E46 that had two codes tripping the CEL and 27 other codes from various modules that the OBD2 scan never indicated.