Changing Spark Plugs from BKR7EQUP to BKR7EIX
 

Recently I installed 450cc injectors, dominator cam and RMW tune on my 2006 JCW. Car ran fine with relatively new (under 5K) JCW plugs: BKR7EQUP. Jan recommended putting the BKR7EIX gapped 0.028 to 0.030. Last night, I installed the IX and gapped them to just under 0.030. Took the car for a drive this morning and it ran like crap. It yo yoed under medium to hard acceleration throughout the whole the rpm range and felt sluggish. Second time I drove the car today the yoyoing was only in the high rpm range. Third time I drove it the yoyo was gone and felt OK, might be down on power. Not sure if it's better than with the QUP.

So before I start mucking around with regapping plugs or switching back to the QUPs: Has anyone experienced something like this after switching/replacing spark plugs?
I'm assuming the ECU adjusted itself to the new plugs, hence it got better. Total driving done was maybe 25 miles.

Yes, the ECU adjusts since you did not reset the adaptations. I run the same plugs in my car without any issues. The NGK BKR7EIX are the better plug.

I always reset all adaptations when I replace plugs.

You would need a bmw tool to reset the spark adaptation like the BavTech tool .

http://www.bavariantechnic.com

I may be going out to the limb here. On a different vehicle, when platinum plugs first came out and Bosch touted how great they are I bought a set. The car ran like crap, and I switch back to the regular plugs. Ever since then I am very wary of any precious metal exotic plugs.

After doing a bit of reading, I recently switched from BKR7EQUP to BKR7E. So far it ran the same on track day.

I don't think ECU will adapt to a set of plugs if they behave badly. It will adjust ignition advance/retard from ping detection.

Well these are NGK not crap Bosch plugs.

Also yes they do have an adaptations for them for a reason. I have had my 2005 for years and know this car very well.

Japanese likes extra gravy with their Tonkatsu just as German likes extra gravy with their Schweinshaxe. :grin:

I am not ponying up for the extra sauce. :wink:

Thanks for the input. I drove it around some more and it seems like it runs norml.