I have already replaced spark plugs and coils...my mini doesnt cold start that well...and when started goes in and out of limp mode...misfires a lot...starting to wonder if the fuel system is to blame

 

Welcome to NAM!

How about some basics - like what year, S or non-S, how many miles, any codes set. People here are happy to help but you have to give us something to go on.

 

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it's an 07 mini cooper s ....it doesnt make boost all the time either....I'm getting a new turbo for it I figured the wastegate is malfunctioning...I dont think air is the problem I have a k n typhoon installed....and with spark already changed it has to be fuel right???? ...unless the timing in it is taking a crap only when it's cold but that wouldnt make sense...if it was the timing wouldnt it run like crap all the time?

 

Could be anything... PCV tube from cam cover to manifold, high pressure fuel pump, turbo, MAF, carbon build up, VANOS solenoids, etc... Need to check for codes with a BMW/Mini specific OBD tool.

 

only codes ever thrown are multiple misfires detected....and misfire in all the cylinders....and the thermostat is bad ....I erase the codes to.see if anything else comes ...its always the same

 

What code reader are you using?

 

autel al619....I know the inside is a little carboned too...I want to take the head off and get it blasted eventually....this is my only car until my nissan is finished....it was fine in the summer...then as soon as it started getting cold it started running like crap

 

it did throw a knock code before I figured it was predetonation after I changed the knock sensor it was gone....keep in mind I have only had this car about 6 months now....its all new to me...I really like the mini and dont want it to die

 

Unfortunately, I don't think that reader is going to grab the specific codes the Mini ECU will capture for these events. You need a reader built specifically made to interact with the BMW/Mini protocol, like a Foxwell NT530 scanner:
https://www.foxwelltool.com/wholesal...installed.html

However, if you get any general OBD codes from your scanner, drop them into the search box here, and get some good information for diagnostics:
https://bmwfault.codes/

 

ok I'll pick one up and try it thanks

 

I there a stupid knock code as well, but it turned out to be that i hadnt tightened the hose clamp enough on my OCC, so i had a leak on the driver side PCV. Tightened all my clamps, cleared code, havent seen it since. Might be worth checking those pesky PCV hoses.

 

Good advice above. Check out the Gen2 section and the Gen2 FAQs. Then read the Gen2 stock problems and issues section. You're not the first person to have these problems with a 2007-2010 R56S, so research before throwing parts at it. If you have the service records, check them carefully. For a 2007S, first suspects are carbon build up and the HPFP. Check the service records to see if the timing chain tensioner has been replaced.