My 06 Mini R53 just past 45K miles and i realize it start to have a sluggish acceleration before 3000rpm, especially on 2nd gerar getting out of corner, it have a little delay from 2500-3000rpm then it kind of jump back to normal. I start to feel that after I installed the DDm works CAI, then I change back to stock but did not solve the problem. I did try to reset the ECU by following the instruction that i found online, but still does not really help.
Anyone have any idea what I need to do next?
thank you.

 

Have you changed the fuel filter ?

Do you use fuel injector cleaner on
a regular basis ?

Just a couple of thoughts . . . . . . . . . . .

 

I am having this same problem too. Im at 47k miles

 

Same problem. Bone stock 03 MCS. No CEL's. Reset the ECU to no avail. Anyone solved their problem?

 

I am schedule a tune up next week, and will let you know what i find.

 

Make sure the By pass vale is working. Mine is having similar symptoms and the BPV is not working properly. I have a very slugish accel in low RPMs once it passes from 2500k it pickup normal.

just a thought.

 

I will check on that, thank you Jav S.

 

Sounds like the bypass valve to me also.

 

I am going to grab a Detroit Tuned BPV. Hope it helps.

 

update: I took my car to Monrovia Mini dealer and the mechanic did not think the BPV is causing the problem, and he also recommended me to keep driving the car until the problem worsen. I don't like the answer but I don't really start argue with him so I took my car back and did a little more DIY.
after cleaning the map sensor (it was very dirty) and my MINI feel much better, it almost does not have any hesitation between 2500-3000. I might be a little bit obsessed with this, for some reason I still think it does have a little flat spot just before 3000rpm. I just clean it on yesterday and I will give it a few more days to find out if the cleaning fix the problem.

 

When last was your supercharger belt replaced?

 

i just confirm that the cleaning did help a little bit but it did not kill the sluggish between 2500 and 3000, it does feel that obvious but still there.
I did have the new supercharge belt put on when i have the 15% pulley installed (about 30000 miles ago).

 

If that is 30,000 miles ago, I would replace the belt. Cheap insurance for $30 and 30K is a lot on the belt with a supercharger pulley.

That's where I would start first. Good luck and let us know what you end up finding out.

And run some cleaner through the car, for sure. SeaFoam it!

 

Running a pulley decreases the interval for belt changes as you are putting more heat into the belt by nature of running it harder. I change mine ever 10,000 - 15,000 miles. I tried not changing it for 25,000 and the car was sluggish, when it was changed the car suddenly felt like it was a new car.

 

You could zip tie the valve shut and see how it feels. I think it is the BPV as well.

+1 for belt change.... More than time for that.

 

I was talking to the tech from Mini and he was mention that if it is the by pass valve problem - I should have more noticeable power lost on the higher rpm range. I only having problem between 2500 to 3000, besides it will only happen when I step on 2nd and 3rd gear, it felt like the gas is not getting enough air, it hesitate just a little then back to normal once it pass 3000rpm.

 

The problem came back - the sluggish between 2500-3000 on second gear is so pronounce my mini does feel like MINI anymore.
after google more on this subject over the last few days, I went back and clean my MAF sensor again on this morning. to my surprise, there are more oil on the sensor again - even I just clean the sensor less than a week ago.
I wonder if anyone can tell me why the oil get into the maf sensor. I do not use the CAI or any other oiled filter after I clean the sensor on last week.

 

Check your oil level.

My car did the same thing. After replacing numerous parts (belt, plugs, plug wires, coil, fuel filter, BPV, Seafoam) - all making it slightly better but not fixing it; I finally checked my PCV valve - filthy with oil...cleaned it...made almost no difference...

2 weeks ago I see my valve cover gasket is bleeding a bit of oil...check PCV valve again...lots of oil...check oil level -> overfull...replace oil, make sure to only add enough...car got a little better every day after that...it's been perfect for the last 3 or 4 days. I guess the oil was over/in everything and took some time to dissipate.

Btw - LOTS of people have been having this issue. And I've had a few too early celebrations myself. I'm really skeptical that this is the solution. I'm actually expecting it to come back out of the blue soon...

 

I double check all oil level and they are fine. I did unplug the power and unplug the ECU but it did not help on the problem.
Did anyone change the Bypass Valve and solve the problem?
thanks,

 

You've not mentioned IF you've got an oil catch can (occ) If so check on the re-routing of the hoses. MANY people followed an original MIS -PRINT by the "a" company resulting in NO breathing of the crankcase and an actual re-introduction of "burnt" oil BACK into the valve cover resulting in high oil levels /foam internally & mystery problems. Also 30m IS way too much on the belt tho you should smell it. All the rest of the above (posts) maintenance / procedures MUST be done IF you expect "performance".How hi are you revving at these gear levels ?? Probably pretty strong eh ?? Plug wires (specially the ones you have) , plugs etc etc. Poor maintenance results in the same kind of performance or WORSE.Start with what fuel your using (91 oct min) and do a COMPLETE tune up, don't believe all you read about 100m plugs etc ~~pull em & take a look. TORQUE everything,tho it's now considered "dangerous" but spraying brake clean etc around "known" intake leak points still works, just be CAREFUL as a little goes a VERY long way. ANY increase in rpm =leak. Preventive Maintenace results in excess check writing and positive performance. Detroit tuned B.P. vlvs are almost a must as this IS a"known" oem fault~~along with a littany of others~~~GOOD LUCK~~ OBEY

 

Thank you Fishead. I just did a complete tune up recently, besides I clean the MAF sensor twice after that, each time it seems help a little. I also notice that car run better in a cooler weather, the problem is more pronounce once the car get hot. car performance well above 4000rpm, it really pull hard, but it feel very sluggish with second gear getting out of the corner, unless I keep the driving the car like I just stole it. Bypass valve might be the next step. I wonder if I should take it back to dealer and ask them to check it again.

 

Doosumpn" <<<>>> You make no mention nor post of your locale. IF possible try to develope a relationship w' a mini shop that you have or can build faith in. By looking at this thread and NOT seeing Way (Way motor works) responding to it I'd say he's taken a well deserved "labor day" cuz by now he'd have jumped in!! Way is the one person whom you CAN trust to address your problems w/o having first developing an understanding. There ARE others and VERY good ones but in dealing HONESTLY over the phone after evaluating this thread alone ~~Way would be your man. If this situation occurs as temps increase ~~LEAKS are the usual suspects do to expansion caused by higher temps and faulty parts and or installation. Electrical failures (wires etc) are highly suspect at greater temps. I'd say it's something (things) quite simple & just overlooked. As you say it seems to improve with each "encounter"~~~~~~cool~~"true love" heh heh; but THAT IS the "way" it IS !!Redline makes the ONLY fuel injector cleaner that I've EVER seen work right before your eyes. never seen another come close. That "resistor" wire on the nologies IS also a culprit, If you've still got the oem's (plug wires) & IF they wern't shot switch them back for a short time. m7 sells their 180 deg thermostat but you don't sound to be a "hands on" owner and that is NOT a job for the un-initiated;but should be thought of. How long HAS it been since you've switched / flushed coolants ?? A combination of distilled water , GOOD anti freeze and water wetter is trully wothwhile not just in temps but also in peace of mind.Are you throwing ANY codes ?? (sel on?)If there IS a REAL problem~~ the computer / ecu SHOULD be telling you~~SOON. $130 bucks for a Mini specific Peake anlyzing tool is another "must have" as YOU will KNOW WHAT that light means and what a mechanic SHOULD be doing or at least properlly diagnose the problem for discussion. 4m rpms in 2nd / 3rd IS equal to you doing 80~~90 mph on the hi-way in 5th /6th W/O momentum. So LOTS of torque exerted on that belt and good cause for slppage. You ARE on the right track~~call WAY~~~~~~~~you won't be sorry. OBEY

 

update: I took my car to my mechanic and asked for his help, and here is what he found out. Oil has been accumulate on the MAF sensor that is causing the sluggish acceleration between 2500-3000rpm. He clean it a few times to find out the oil is somehow end up at the MAF sensors. He mention the oil might be coming out from the supercharge or the engine. I am thinking to take my car back to dealer and let them find out more detail. But I also wondering if the warranty will cover the repair if the supercharger is leaking oil. I did install the 15% pulley almost two years ago, and it is no way the original pulley can put it back. Is it the time to sell my Mini if it is really leaking supercharge oil??

 

R53s have a MAF? Where is it located????

 

Curious about this myself considering there is nothing between the intake and throttle body. Also, how could oil coat this even if a SC seal was bad? I could be wrong, but a search turned up nothing.....

I'm thinking you need a new mechanic. Also, why would you sell your MINI just because of a small problem that could be resolved? +1 for what Fish said, give Way a call and talk to him.