Over the weekend my car threw two codes: P0302 and P0313. I had the guy at Advanced reset it and it has returned (the P0302). The '313 was undoubtedly added to the mix because I was low on gas at the time, but have since filled up again.

Fearing the worst, I checked compression on all cylinders last night and all are normal. That leaves ignition and fuel delivery. The Bentley manual describes testing both the coil pack as well as the fuel injectors with an oscilliscope (which I do not have). Is there a different way to check which part is faulty? Once the code goes up the car runs smooth again - presumably because the ECM has shut off fuel to the offending cylinder.

Also, is there a way to reset the code without using a scan tool, or does the car test all systems on startup and make a decision each time whether or not to deliver fuel to that cylinder?

Thanks for your help! I'm putting up a separate thread with my coolant issues. This has all been coming to a head slowly but after changing the S/C oil I think everything's been accelerated! How maddening!

 

The ECU would not "shut off" fuel to the cylinder, and yes, you have to manually reset the code, just pick yourself up a generic reader & reset tool, the one I have was only $30.00 or so and they're pretty much invaluable to have around.

As far as testing, once you get your code cleared, just start with the basics, check your #2 plug, if it doesn't look any different from the others, swap it's position, & see if your code changes positions too, then, same with the wire, clear code, swap positions, then the coil, clear the code, clean the terminals, see what happens, lastly try an injector position swap.

Good luck.

 

Do leak down test, as this is a better then doing just a compression test. I also agree with what BlwnAway suggests.

 

A leak down test is more specific in pinpointing the condition of an engine and if there are problems, it can pinpoint the needed area of attention. A leak down test is performed with a special gauge and manifold set. It consists of a calibrated pressure gauge and a pressure regulator and adapters to connect it to the spark plug hole. Compressed air (or nitrogen) is fed into the gauge and the gauge is calibrated against a zero reference (no air leakage). The adapter is then screwed into the number one spark plug hole (with cylinder #1 at TDC compression) and the gauge is attached. As soon as the gauge is attached to the adapter air will begin to fill the cylinder. As this happens, the gauge will begin to indicate the amount of air flowing into the cylinder.



If air is leaking past the rings, or the valves, or the head gasket, we can directly read the amount of leakage and can easily find the leak. If there is air blowing out the PCV, we have a ring leak, if it's coming out of the exhaust, we have an exhaust valve leak, and so on...

 

You may wany to consider the leakdown test after the simple electrical tests & before the injector swap, just simply because our cars "normally" don't have many injector failures that aren't attributed to more than dirty fuel / clogging, the injectors themselves are usually prety solid.

 

The Bentley says it does (unless I'm reading it wrong?). I can't find any other reason to explain why it runs like crap for the first few seconds of startup then smooths out like normal. It's changing something.

A few times the DSC light has also come on at startup and will not turn off unless I turn the car off and then on again - then it stays off for the duration. I didn't think DSC had anything to do with the CEL.

I'm assuming I have to take my car somewhere so they can do the leakdown test? I did the compression test both wet and dry and noticed no difference in readings (trying to rule out rings). What could cause a spontaneous failure of valves? In all my years of turning wrenches, these things have failed gradually- then again, this car doesn't surprise me anymore.

If our injectors are usually pretty solid, are these symptoms typical of a coil pack failure or faulty spark plug? These plugs have been in for only 10k miles so far (they are NGK Iridiums, don't recall the number but it's the same heat range as the JCW factory kit as I have a 15% Alta pulley).

The coil pack is an MSD that went in at 40k (almost 102k now), and I still have the stock one. I suppose I could swap coil packs too and see if that makes a difference?

Can any of this be connected to my coolant issues?

Thanks for the replies - it gives me something to get started. Besides fuel, ignition and compression..I don't know what else it could be.

 

Prob. should have clarified that, it doesn't shut off a cylinder, but yes it makes adjustments for failures best it can, absolutely swap coils first, the only thing about the plugs is the possibility of having fouled one from over fueling because of an electrical issue, with the compression check I would first guess that the coolant thing may only be the culprit from the leak / steam maybe damaging something (coil) simply by getting something wet.

Oh, and minor faults have been known to trip the DSC light every now & then.

 

Googling Mini problems is like googling health problems. I came across this:
https://www.northamericanmotoring.co...-and-dies.html

Chipped camshaft? Camshaft Position Sensor?

The plugs all look the same near as I can tell. No fouling, no worn tips or gaps that look out of whack (were factory gapped and worked fine thus far - no sign of mechanical damage).

Coils can be damaged by moisture? How about wires? I'm using the wires that also came with the Alta kit but they appear fine albeit a bit dirty. I always use dielectric grease on the connectors so they don't get corroded and they appear to be OK (I only looked at the terminal for the #2 cylinder and it looked fine.)

 

Update:
Cleared code P0302 while the car had been sitting all night. Changed the coilpack. Restarted and it ran rough for a few seconds and threw the code again. Shut down after 1 minute, cleared code, restarted. No code for the entire 45 minutes I let the car idle.

Started the car this morning, ran rough for a few seconds, no code (yet) but the DSC light turned on. Let it run for 1 minute, shut it off, restarted. No CEL, no DSC. Didn't stick the reader on there to see if there's a latent code that hasn't tripped the CEL yet.

I don't think the problem is solved, but I can almost without a doubt say that it's exclusively a COLD START problem. Now what causes that?! I've been doing some reading that says it could be the camshaft position sensor - any merit in that hypothesis?

I plan on swapping plugs and wires tonight. Is there any way to test the wires for failure, aka resistance above a known point?

 

Update:

My previous theory of it being a cold start problem is BS. It appears more likely to happen when cold, but not necessarily.

Yesterday I started it after it was sitting in the cold for about 5 hours and it misfired so bad I had to shut it off, SES was flashing. Restarted it immediately and it ran fine.

Last night I swapped plugs 1 and 2. I probably should have put more grease on the contacts but I wiped off what was there (it was dirty), and installed everything. Started up last night with no misfire, and this morning as well. I cleared the code yesterday afternoon so it had two starts on the original setup, and two on the new one and haven't thrown a code yet.

This is the oddest thing ever.

 

Maybe that has been your problem all along, too much grease.

 

I didn't know there was such a thing as too much grease. I started it again at lunch and it started to run rough so I shut it down immediately and restarted. Runs smooth; no codes.

How long do plug wires last? I'm pretty sure they are magnecor wires from Alta. Installed about 60k ago.

Is there a way to test them based on resistance?

Could a faulty sensor (cam pos or crank pos) be causing this? I replaced the leaky o ring on the crank sensor when I did the s/c maintenance.

I have to check the schematics in the Bentley again...this problem seems to be electrical or engine management related...

 

So was this the faulty cam sensor? I'm having similar issues. Thanks.

 

I have been having the same problem for about a month also on my 2009 Clubman S with about 54,000 miles on it. The intake valves were extremely dirty, just caked on crud... I had them walnut blasted, and while the car has a lot more power now and is more responsive, I still have extremely rough idling after starting the engine about once or twice per week. The dealership replaced the timing chain, guides, and tensioner about 4,000 miles ago, so that should not be contributing.

Usually it happens when the car has been sitting for an hour or more, and the two worst times were when the car was sitting overnight, but 9 times out of 10 it starts totally normal. When it does run rough it is so rough that the RPMs are below idle and stepping on the accelerator does nothing. The engine will sometimes stall out and I get a CEL (check engine light). The codes are:

P0304 Cylinder 4 Misfire Detected
P0302 Cylinder 2 Misfire Detected
P2781 Misfire Mult Cyl Max
P2779 Misfire Cyl 4 Max
P277D Misfire Cyl 2 Max
P2783 Misfire Mult Cyl Error
P277B Misfire Cyl 4 Error
P277F Misfire Cyl 2 Error
P2773 Misfire Cyl 1 Error

My local shop also noticed that there is a brief puff of black smoke out the tailpipe when the engine is first started. As the intake valve cleaning did not help, I am going to try changing plugs, but I may also look at the wires and coil packs to see if they're dirty. My local shop suspects the high pressure fuel pump, but my dealership insists there is usually an CEL code for the fuel pump when it is failing.

It's just so puzzling how this problem started all of the sudden and it is affecting cylinders 2 and 4 and maybe 1. I am hoping it's just bad gas or something. I just filled up a couple days ago and haven't had an problems so far...

 

Try posting in a gen2 forum...then motors and issues in the 2002-2006 mini are VERY different than the newer ones!! Good luck!!

 

I wrestled with this code and tested everything but...

It was a misfire caused by a clogged fuel injector. They aren't kidding when they say you should rund fuel injector cleaner through your gas tank. I ended up flushing my injectors the hard way but they seem fine now.