Hey guys. Got another problem. 05 R53, 17% pulley, elsewise is stock. When going full throttle in 2nd and third gear (most noticeable) the car stutters through 2k and 3k rpm. once past 3k rpm the car pulls hard. No check engine lights, and resetting the ECU did not fix the problem. Would like to avoid throwing parts and hoping it will go away, hopefully someone has had the same problem. I can get a friend to record a video from inside of the car if it will help.

Thanks everyone, hope its something simple. I dont know why it wont throw a code??? ;(

 

I just posted this exact same problem.. I have no idea how to fix this

 

I read your thread, from what you're explaining, I have a different problem than you. I am leaning towards a bypass valve, or a MAP sensor as a few months ago I got a check engine light for something related to MAP and it went away a few days later.. odd..

I just don't want to throw money at a problem without getting feedback from other people.

 

I had a similar problem, but mine was around 4-5k rpms. I literally replaced everything. It ended up being the timing chain tensioner!

And it actually makes sense why it would be the timing chain tensioner if you think about it.

 

Thanks Mainstreet. Before heading into work today I'll do what the ModMini video does to diagnose a bad one. I thought face lifted minis rarely had this problem?

 

went ahead and pushed on the bpv and it is very hard, so i dont think its a problem with that. how many ftlbs am i supposed to be feeling for? its pretty stiff, but still no code.

 

same here but mine is an automatic. i only get around 15

 

check your throttle housing to the supercharger! it's just held onto the supercharger with one bolt... pulled my front end apart yesterday and that plastic bracket the bolt goes into was broken so the housing feeding the supercharger was very loose!!

 

you havew the part number of the throttle housing? is that the bpv?

 

When's the last time you have checked/changed your spark plugs and wires? Sounds like it could be a spark issue that is causing the stuttering.

As far as the engine not wanting to pull really hard until you get the RPM's up over 3,000......that's kind of the nature of the beast. These little motors we have in our mini's don't really start making much power until you get the rpms up....and you won't get full boost until you get the rpms up over 3,000. But the stuttering thing....it shouldn't be doing that.

 

by pull normally i mean like it should. with the 17% pulley boost comes on at about 2500 rpm. i dont think its the spark plugs, wouldnt it have thrown a code for a misfire? I will pull them out soon as theyre getting replaced with a new coil and leads.

I am still confused. No codes, and it seems.. random. some days its really bad. others it barely does it.

 

I read where you said the BPV had sufficient tension, but still may not be fully closing, and could be sticking.

ralph801 is referring to the Supercharger intake DUCT. There is a green jam gasket and one hex screw that holds it down where it attaches to the SC...but as your symptoms are somewhat intermittent and no code, the BPV seems to be a logical place to start.

 

that is what i am leaning towards but I dont want to just throw a new BPV at it and hope it fixes it. Maybe I will though, I work at a bodyshop and get wholesale prices from BMW so I will see how much it is and see if I can justify it.

 

Get a Detroit Tunned bypass valve...much cheaper than oem and works better, builds boost faster.

 

Not exactly...
IT IS AN OEM unit...
Just has a stiffer spring installed...in a NEW UNIT FROM THE OEM...
Was made for pre 2004 cars with a very weak spring installed from the factory...
But at some point around 2004, mini themselves started using a stiffer spring....slightly weaker than the REWORKED DT unit....
For some, the DT unit is too much...it can slam shut, and make driving with finesse harder...
For some it is right, just know what you are getting.

 

i am going to try to record a video so you guys can HEAR the stuttering. i have one and im uploading it now.

 

Don't over think this. Start at the simple. Get a scan tool and check for codes even if your CEL is not on. You might have pending codes. Then check your spark plugs. Pull them out, and if you don't know exactly what to look for, post an image of them and we'll have a look. A bad BPV typically doesn't cause 'hesitation', as in a jerky reluctance to accelerate. That sounds more like ignition problems to me. Don't worry about the wires just yet, they're rarely the culprit, unless they've been chewed by a resident mouse.

 

I have checked the codes. none, besides a stored one for my broken thermostat (which mysteriously works again???)

I will pull out the spark plugs when I get to work and post pictures, along with the video so you guys can hear the hesitation and what I am describing.

Thanks to everyone for being patient with me. I am trying to get this car all sorted before I visit Helix for my tune, and I don't want to throw money at it. Again, thanks everyone.

 

You can eliminate the possibility of it being a bypass valve with a .02$ zip tie....
Zip tie it closed...and see if it does it....do it the wrong way, and you will drive like a slow r50...lol...
Only real thing is you might loose 1 or 2 mpg while it is ziptied to be on boost all the time...purpose of the bypass valve is to "unload" the sc when the motor does not need boost, like low rpm running, idle, etc...
+1
For keeping it simple...
A thermosts will stick...they are just mechanical...but I'd change it before it sticks the wrong way and gets you stuck with an overheat if you have been having issues.

 

http://imgur.com/a/Oek9s

video

right at about 1:15 (listen carefully) you can hear what i am talking about by stuttering.

Spark plugs say its running lean (all stock with a 17% pulley) but still no code for a misfire and totally random. i have had this pulley on for 4 months and this problem started 3 weeks ago.

Also, ignore oiley 2nd spark plug. I never cleaned my valve cover after replacing all of the gaskets.

 

So, a few things I forgot to post.

I run 92 or 93 octane, and I drive roughly 20 miles a day. 7 of it is high way doing 65+ and I average 18-20 MPG. Is this any help? Does anyone have any more ideas? A while ago I had a code for something involving MAP sensor. (which is no longer stored on the computer like the code for my bad thermostat, and the light turned off and hasnt been back since 2 months ago. completely strange)

P0108

This happened when I was "going hard" with WOT for 1st, 2nd and 3rd gear and then it came on.

Should I just bite the bullet and replace the BPV, spark plugs, and both MAP sensors? Also, for further clarification I have a belt sized for a 17% pulley that is less than 10k miles old.

I have new Alta Silicone couplers and I plan to put them on during work today, figured it was about time for them. Any other thoughts? New plugs, BPV and MAP sensors are like 200 dollars which is a huge chunk of my budget.

Thanks everyone, also does anyone know where to put a zip tie on the BPV to keep it closed?

 

That's not a BPV........if I had to guess, I would say it's a problem with your spark plugs, wires, or coil.

The only thing a BPV does is bleed off boost when the motor has no load on it (pulling manifold vacuum)...and when you stomp on the gas, the vacuum drops...the spring in the valve pushes it shut, and the supercharge builds boost.

I guess the BPV could be bouncing around because the spring in it is broken, but you said you checked it and it's snapping shut ok..right?

 

Yes. It is pretty hard to push the pushrod in from the underside.

It appears it has something to do with fuel... it is most apparent (the stuttering) when I put it in gear, and let off the gas totally so im just crusing until 2grand and flat to the floor. misfires appear to be worse today (heavy rain, 31 degrees) AND when I was doing it for about a mile today I could smell fuel without my windows open. It was very slight, like how sometimes old oil smells when it has gas in it.


So.. I should just replace everything and get it over with? Any reason why it doesnt throw a code and why its better on some days than others? Is it misfiring through the whole rev-range and I just dont notice it at higher RPMs?

Thanks everyone. So much

 

Start with the easiest/cheapest stuff first . Replace your plugs and wires...and go from there. I think that if it was fuel related....the stuttering would get worse as rpms climbed, not better.

Do the plugs and wires....

 

When I said fuel I meant ignition or spark plugs.