I've been getting the P0302 error code every couple of days along with P115C. When it happens the car has much less power, like the turbo isn't working. I assume this is because it's only running on 3 cylinders! It lasts for a few minutes, then the car recovers and runs OK. I checked the #2 spark plug, looks fine (they were replaced 6 months ago). It's been raining a lot lately, so I though it might be a moisture issue. I removed the coilpacks and dabbed on a bit of dielectric grease before reattaching (I hadn't done this back when I changed the plugs). Then I went OCD and removed every electrical connector under the hood, dried with a hairdryer and applied dielectric grease before reattaching. The car ran fine for another day, then I got P0302 and p115c again. Each time it is cylinder #2. Now the p115c is nothing new - I have had that intermittently for over 2 years and the dealer has not been able to find the problem (I actually gave up and just live with it). There were never any symptoms accompanying p115c. The light would come on and go away after a day. I don't know whether the 2 codes are related or if its just a coincidence they are appearing together now. So what should I check next?:idea:
Last week my R56 gave me the codes P0300, P0301, P0302, P0304. The car was hesitating and stumbling on acceleration. Talked with my coworkers, we are general aviation aircraft mechanics, decided it might be some bad fuel. Anyway put about 1 cup of 91% isopropyl alcohol in the tank, stumble went away. Cleared the codes, they haven't come back, I'm almost done with the second tank of gas since:fingerscrossed:. Might not help with the P115C code, but if there has been alot of rain, you might have picked up some water in the fuel. The alcohol is cheap, might be worth a try! Joel
* MINI DTC P115C (0x2775 or 0x2B56 or 0x2B58 or 0x2B5C) - Mass Air Volume Flow 'A' Too Low The ECU is still seeing too small of inlet volume of air passing the MAF. Which means there could be an opening / leak after the MAF allowing unmetered air to enter the engine. It could be: a.) the MAF is shot (rare, but occurs) b.) there's a leak in the intake system - a pressure check will confirm that c.) valve cover leak / crack, which is becoming a more common occurance d.) or... do you have a catch can installed? - Erik
thanks Joel, I'll try some fuel system treatment to see if that helps. I also swapped the coilpack on cylinder 2 with cylinder 1 to see if the miss-fire changes to cylinder 1. for the p115c: The dealer replaced the $600 MAF, but the CEL came back a day later (they refunded me for the part). They were unable to find any air leaks using a smoke test, but I don't know if they checked the valve cover. I had a catch can, but removed it a couple years ago. Had the CEL with it and without it. Checking the valve cover sounds like a good idea, thanks! Oh, one other thing I forgot. When I replaced the bypass valve last spring with the WMW bybass valve, the p115c code didn't come on for 5 months - usually its a weekly occurrence. I thought for sure that had solved it, but the CEL eventually returned. It seems unlikely that the new bypass valve already has issues though, so I think that was a coincidence. Maybe. :skep:
:cornut: Do you have an after market silicone intake hose(between the air cleaner and the turbo charger)? I had the old Alta silicone hose that started collapsing after about a year and had to replace it with a metal one. Mine was throwing the 115 codes especially after rapid slowing from 30min-1hr sustained high speed. Jason
I had P115C and it was eventually traced to carbon build up on the intake valves. I had it walnut shelled about 12 months earlier and had a catch con on. Another round of blasting solved it. Well, for another 10k miles...
Hard to remove that stuff. Unfortunately I'm well out of warranty now (actually I was past warranty the first time, but they good willed it). I'll try to keep it going for another year with sea foam. Update on the miss-fire p0302: it hasn't reoccurred since swapping the coilpacks, but I'm still getting p115c every couple days.
things have gotten worse. getting p115c error code every day and accompanied by intermittent power loss. I installed a boost gauge to monitor what is happening. Occasionally, when I pull away from a stop, I get no boost at all - boost gauge doesn't rise above 0. Sometimes it recovers right away and when I shift into 2nd gear it's fine. Sometimes the lack of boost will last longer and is accompanied by error code p115c. Boost will return after clearing the error code with a code reader, or after a few miles of driving if I don't. I thought: faulty BOV, replaced it, no change. My mechanic said it was the wastegate, which he replaced - no change. We checked for leaks in the intake, intercooler, everywhere - no leaks. We think that the ECU is sensing a problem and so is cutting boost. Next I'm going to replace the valve cover and gasket as it appears there is a small oil leak at the right side of the valve cover. I really don't think this will help, but I'm clutching at straws now. History: MAF was replaced by dealer a 18 months ago when I first had p115c (I had no power loss then only the CEL) and also pulled the head and cleaned the carbon deposits and replaced the timing chain tensioner again. p115c returned a couple days later. Warranty was expired so I just lived with the cel.
OK, time for a FINAL update. I replaced the valve cover (which comes with a new oil cap by the way:wink aaaaaaand.... wait for it...... check engine light (P115c) came back on.:mad2::mad2::mad2: While at the dealer getting another oil leak fixed, I asked them to have one more go at it. They said there was a PUMA on that. I said there's a mountain lion under the hood? No, a PUMA is like a technical bulletin that says someone else had the same problem and they fixed it this way. So they tried that and replaced the intake manifold part #13712753078 (that's number 8 in the picture) Did that fix it? no. They said they could figure it out eventually, it might be another thousand or so, but they'd get it. I said don't bother, this has gone on too long already. So that's it, I'm done with it, I've finally had it, I completely give up.
So I stumbled across this thread in hopes to find exactly whats wrong with my '11 MCS. I keep getting codes P0300 and P0304. And the worst part is the car was shaking when trying to drive home and not running smooth AT ALL. I parked it since today and left it outside in the rain haha. So my valve cover needed to be replaced due to a weird whistle sound every morning at startup. Detroit Tuned helped me out by diagnosing it and telling me I needed my VC to be replaced. It is a pretty EASY job to replace the stupid thing so I did it with a buddy of mine who owns a R56 himself. NOW, when we were done I was wondering if I should have replaced my spark plugs since they slightly looked worn out but normal wear. I looked at my coils and I'm going to take the cover off tomorrow morning and try again if I can start it up with no issues. If that doesn't work, I guess I might try some NGK's 5992s. Anyone else have any ideas, I keep reading vacuum leak, which isn't the cause and fuel injector? Thanks for the help, if any help lol.