Hi everyone,

New user here, just bought my very first Mini 4 months ago and have *really* been enjoying it! It's a 2013 R56 Cooper S hardtop, with an automatic transmission and 36,000 miles on the clock. It's been a great, well taken care of car that runs and drives like it should. I spent months looking for a good one.
However, about 3.5 months in, I was driving one night, and leaving a green light was accelerating up to 60 mph, and about half way (30-40?) there was some hesitation in maybe 3rd gear at 3,500 rpm. The car then went into limp mode and ran very rough, and the yellow check engine light came on. Did a bunch of research and hooked up a code reader, which said it's ignition coil # 4, so I bought a new coil and replaced it, to be able to drive it to the dealer where they wanted to replaced all 4 coils and spark plugs under warranty. Great!

They did the work, as they say it's recommended to replace all plugs and coils when just one goes bad. The reason I'm posting here, is that the car now doesn't feel quite as powerful as before. The "kick" in my back that pushed me into the seat with each gear change -- just isn't there anymore. The car isn't slow by any means, and runs very smooth, but it doesn't feel race car peppy like before (which blew me away and put a smile on my face with every previous drive). I wondered if it was my imagination, and I've given it a couple weeks of driving, but each time I do it confirms my thoughts more and more. It's definitely not like it was.

I've done lots of googling and reading threads about spark plug brands and gaps (especially on this site), but haven't found a definitive answer that that's the problem. Has anyone else experienced this? They installed OEM parts at the official Mini dealership, so what's the deal? Is it the spark plug brand and/or gap that could be the problem? I don't know what was in there before, but I have to assume it was factory. The guy at the parts counter (before I learned the warranty was still in effect) was ready to sell me Champion brand spark plugs, so that's most likely what they installed. Part # 1212 229 3697 for the plugs, and 1213 861 6153 for the coils.

I'm planing on taking it back there, but wanted some input on here first. Can anyone please shed some light? I just want the car to punch me in the back like before.

Thanks for your help!

 

Possible that prior owner had a tune installed on the car in the ECU. During dealer work that got overwritten. Anyway to contact prior owner to find out if that is the case?

Does the work order mention anything about updating car software?

Are you saying MINI parts wanted to sell you Champion plugs? That seems odd.

It obviously could be other things as well.

 

I doubt there was an ECU tuning before. The previous owner was a 24 year-old college girl, who owned it from 10,000 miles to 34,000 miles. I don't think she was the tuner/racer type, as the car is cosmetically stock. No idea about the first owner though, who had it the first 10,000 miles.

Nothing is mentioned on the invoice about software updates. It just says "inspection not done due to MPI system being down."
The service history shows that one of the coils was replaced by an official dealership in March 2017 (but not all coils, or any spark plugs), so it was touched by a dealership as recent as 9 months before I bought it.

 

Can you do an actual timed 0-60 run and see how that compares to the numbers for stock? It is very possible that the smoother running makes the car *feel* slower when it is simply smoother. Honda and Toyota did this on purpose with their VTEC/iVVT calibrations - they engaged the faster cams too late so that you got more of a kick and made the changeover more noticeable despite it being slower overall.

 

It ran totally smooth before the hesitation and engine light that night when the coil went bad, and still felt "powerful," like what I'm trying to get back.

Another way to describe the difference is that it's like the turbo isn't kicking in as hard or something. Like the boost has been turned down. But I can't imagine they would have changed anything at all. They just did the coils and plugs, and replaced the coolant at my request.

 

Sure, but we can't be much help when the only symptom is a feeling. Hard facts are much easier to diagnose, so an increased 0-60 time, short-term and long-term fuel trims, decreased MAF reading, etc, are much better to build a diagnosis off of. The obvious stuff like a misfire from a bad spark plug or disconnected wire doesn't fit because there's no check engine light that you mention, so we are all in the dark for now.

 

Well, I guess I was hoping for a confirming "yep, it's the spark plugs, same thing happened to me" kind of answer from someone. I'll get it checked out at the dealer, hopefully this weekend. What worries me is that they'll say "alright, we looked at it and everything's fine, nothing's wrong." and I'll be stuck with the lesser power.

 

Did you ever find out what caused the downgrade in performance??