Hesitation Under Hard Acceleration
 

We've owned our 2013 Cooper Paceman S All4 for 2 months now.

It had 50,000kms when we picked it up. I noticed while driving it in higher gears and hard accelerating there is hesitation from the engine. Worse if you hit a slight hill. Noticeable between 2 - 3k rpm.

I replaced the spark plugs. I installed some NGK Platinum 90223 plugs which were the ones that the auto retailer said were recommended.

The hesitation is still there and now after a lot of reading on here i'm paranoid about the plugs. Should I have installed the 95770 irridium plugs instead?

I'm also wondering if its an issue with a coil or carbon build up. I'm not getting any misfiring but its really annoying when you accelerate and it feels like it skips a beat erratically.

Basically looking for an answer about the plugs, which is best to fit?

Any help is much appreciated.

I had a stumble around that RPM under hard accel. I pushed the car harder to trigger the CEL. Its a misfire you have, I lost coil 1 . As far as the plugs go, I selected my car at my brothers shop PC to order parts and it gave me Iridium plugs.

Do you have a CEL ?

You have to push to stumble and stick with it. I just got another coil pop as bad. She gave a code the other day, I cleared it. Today I got on her to trigger the light just before I got to my brothers shop and but I couldnt.
I have OEM coils coming.

I'm dealing with the same thing on my 2012 Countryman and my wife's 2010 Clubman. I was getting some stumbling last year, so I replaced the plugs and coils in both, and it went away. Then we moved from Florida to New Mexico and they're doing it again. I didn't buy OEM parts, so maybe that's the problem. I have 4 OEM plugs that I'm planning to install this weekend, and if that doesn't help I'll order OEM coils. If that doesn't help, I don't know, I might just live with it.

Anyway, try replacing the coils if you haven't yet. Just replace all 4, they're not that expensive.

Im running Denso Iridium plugs and delphi coils. Delphi makes the coils for Mini. But I decided to order 4 from minipartsdirect.com best price I could find. If they have the same number as the Delphi's I have now it doesnt matter OEM or not.

I have say less then 10k miles I on them .

It could be so many things with these newer prince engines. Doubt carbon build up though. You have newer design.

Could be a fuel pump issue, ( high pressure or low - I think theres an extended warranty for HPFP ) could be air sensor issue, could be bad coil, could even be issue with Turbo.

Meantime, while you spend $$$$ throwing parts at a problem which doesnt go away, you could just go to the dealer, have it diagnosed properly and get it over with...

what oil are you using and do you know what its flash point is? i am asking this because it might be just bad oil, burning at operating temps and decreasing the octane rating of the gas.

Mobil1 0w40 euro I had LiquiMoly before than Castrol Titanium before that, before that Mobil1 0w40 without smoking .LM and C smoked and C died at 3000miles.
Today my Mini OEM coils came in at 55bucks per. Totally different look compared to the Delphi aftermarket coils. I pulled a plug and ran the number, turns out the parts supplier sent the wrong plugs. The Denso plugs were for a Toyota.
New NGK plugs gapped at the proper .26 thats called for my engine as opposed to the .42 plugs Denso had listed

I drove home in S mode and beat the snot out of her. No misfire :)

So, after more driving the initial problem that i described as hesitation under hard acceleration is more like hesitation in higher gears even with just lightly accelerating. 1st and 2nd gears it pulls really hard but once you are up over 50mph acceleration is not smooth. the hesitation is random though and i'm not getting any CEL. I kinda wish I would that way I would have something to show for it.

In sport mode the hesitation is slightly reduced/

Any ideas or previous experiences or where to look next?

Did you ever replace the coils? My money is on coils.

I replaced the spark plugs and coils on both my R60 and my wife's R55 this morning with OEM parts vs what I had purchased previously. I didn't have any issues when I drove mine to lunch, but it's too early to say whether it fixed the problem. It typically doesn't do it much in the mornings when it's still cool out.

I'm in a similar situation. Recently replaced the turbo with a new Cardone unit. The old one had a completely worn out waste gate and was causing a 2C57 code. Now the code is gone, but it's having hesitation and bucking under acceleration. I don't remember this happening before, but that could be because it probably wasn't making nearly the boost that it does now which is making it more noticeable.
It has new NGK plugs and Delphi coils, so I do not think it is ignition related. Had the HPFP replaced about a year ago when the 2C57 code originally started.
Also has a new pressure converter and diverter valve. Stock ECU

Just wondering what was causing your over boosting issue and what you did to fix it?

I just needed to adjust the wastegate.
If you have a way to monitor boost pressure, you can tell pretty quick if you are making too much or not.
stock boost pressure tops out around 11psi, with overboost, up to around 15.

I thought the computer controlled the boost via the pressure converter?
I also thought the rod on the wastegate was adjustable to set the amount of play between the diaphragm and the wastegate valve itself? (I've never messed with internal wastegates, It's always been externals that have replaceable springs for setting your base boost level.)

Where can I easily tap into the intake to get accurate boost readings with a mechanical gauge so I can see how much boost it's really making?