Half check engine light came on. Checked code P0303 (misfire cylinder 3) hoping/thinking spark plugs. Plugs look a little warn, so I changed all 4 (NGK iridium). Erased code with reader, started it up, cluster is still showing half CEL. Checked reader throwing no codes. Drove it around for 30 minutes checked OBD reader still no codes but light is still on.... My questions and concerns are

Do I have to reset the CEL light on cluster/dash manually? (I thought reader does that when you erase the code)

Any other problems with P0303 I should be concerned with?

Maybe the problem isn't fixed. How long will it take to throw a new code?

Please help..

Any information from Cel light to p0303 misfire is welcome! Knowledge is power!!

 

You have left out the most important info, Non-S, Mini Cooper S and year?

 

Sorry about that,

2007 Mini Cooper S (r56)

 

Now for the mileage, you should know our N14 engines burn quite a bit of oil, 1.5 quarts per 1500 miles. I don't know your mileage but my engine began misfiring randomly with no CEL at all at 50,000 miles do to carbon buildup on the intake valves. Get into the habit of having your valves walnut blasted every 30-50,000 miles, this could be the reason why your getting a CEL. Other than the misfire code how is your engine behaving?

 

Are you talking about the half engine symbol that shows up in the tach display? If so, that is the reduced power symbol, not CEL. If that is what it is, you won't get codes via the OBD. You can drill down to get some codes, but usually they aren't very helpful unless you have access to MINI software to read all the codes and pull other info.

 

There is a code, but your reader can't see it. You'll need to get to a dealer, or to a good independent mechanic who has one of the MINI-specific (or BMW-specific) readers.

 

Hey everyone thank you for all your replies.

I Drove it to work (50mil) this morning and by the time i got to work the indication was gone...

Stopped and started it up again 2-3 times to make sure it was gone. The indication did not pop back up. Checked BC options engine check said "OK"

Hopefully it was just a matter of driving it around for the computer to reset/acknowledge the status..... i dont know

i'll drive it home and see if the light comes back on later but i will double check with a dealer aswell.
Thanks everyone!

 

Keep us posted if anything else pops up. Mileage?

 

Thanks i will.

Mileage : 99,875 almost to the 100,000 mile mark fingers crossed!

 

Have you ever had your intake valves walnut blasted? If not you're sure overdo, it's a common issue with N14's .

 

Check coil packs as well.