First off, don't ask me to do a search, I have, using ever keyword I can come up with. If you know of a thread, give me a link, or the keyword, thanks

The issue; my wifes 05 Cabrio Cooper has been backfiring through the throttle body/injectors on cold starts. Not all the time, and it happens for days on end, then goes away for weeks, then returns.

The dealer has looked at it twice now, no codes are showing, and even when they keep the car overnight, it will not do it for them.

The kind of gas does not seem to make a difference, all premium, whether it be 91 or 93 octane, top tier or bargain brand.

We are running some fuel injector cleaner in the last tank of top tier gas we put in it, and it stopped doing it for over a week, then this morning it did it again, same tank.

It only does it on the first start of the day, and will not do it until the car has sat for many hours, overnight. The outside temp. does not matter.

If anyone has had this issue, let us know, if you know of a fix, even better.

Thanks,
Mark

 

Hmmm... backfire through the throttle body is generally timing related. Can you get it to do it on a regular basis? Mayne start documenting things such as time shut off, time of day, fuel level, etc... Something has to link back to it eventually.