I bought this car last week and it drove really good. I was able to log about 250 miles on a full tank of 91 octane filled at my local shell gas station in about 4 days. Not sure if its relivant but my wife decided to drive it on the 5 day shes not very good dirving manual and did stall it about 5 times.

Yesterday i was driving the car on the highway i was going about 75 and decided to pass a car and completely lost power. The engine light came on and I took it in to check. I got the usual p0301 and p0303. Thinking maybe spark plugs needed replacement i checked them out but they have just been replaced with ngk laser iridium. They all looked consistent. I did not however check the gap. If some can tell me the gap that would be great. So i cleared the code and swapped the coils. Drove around and made it miss fire and the engine light came on again, checked the codes and they were now p0302 and p0304. I ordered 2 new coils. Cleared the codes and drove it thinking i had fixed it and the check engine light came on again with the same p0302 and p0304 codes. the miss fire happenes around 2-3k rpm after 1st gear. Inthe rest of the gears in the high rpm its not present. For clarificaton cylinder 1 is on the passenger side. Im ruling out the sparks since the codes followed the coils, i dont think it was a bad batch of gas since i drove 250miles on it. I will add some techron to my next gas tank. I made sure the coils are seated good.The car starts fine and idles fine no hesitation which makes me think its not the fuel pump i check the air filter and it pretty new too. Any idea would be great. Thanks in advance.

 

We need more information, do records indicate it's ever had the intake valves walnut blasted? If your intake valves have oil coke all over them this will cause mis-fires, for the record cylinder 1 & 2 usually are much more coated with oily carbon deposits, have a look what mine looked like after 62,251 miles here. You're running an N14 engine notoriously known for drinking oil. My N14 engine consumes half a quart every 1000 miles. That means after only 3000 miles if you're consuming half a quart of oil every 1000 miles and you don't add oil after 3000 miles, you're down to three quarts of oil which is a bad thing! Get used to storing a few bottles of oil in your Mini.

 

Well I don't have much more information as I just bought the vehicle, but I doubt the valves have bee blasted. I decided to start back from square 1 and put the old ignition coils and check the engine codes for the miss fires and then put back the new ones in I had bought in the corresponding codes. I then added a bottle of techron and filled up the tank with 93 octane from a chevron station and also did the seafoam yesterday. It all seemed to work as I have driven it for about 70 miles with no loss of power. I really hope these things fixed it. I'll keep you guys up dated. As far as oil I haven't seen any loss, where exactly is the oil suppose to come up on the dip stick when full? Mine is all the way to the top of the plastic piece on the tip of the dip stick (orange piece).

 

You purchased a car blindfolded with no records?

I have never heard of an N14 engine that doesn't consume any oil, even the manual says it does. 1 quart per 1000 miles is consider normal by Mini, of course their full of ****! It's just a bad, lazy design! I would never recommend to any of my friends and family to buy a Mini Cooper S let alone a used one. Sea foam and Techron does nothing, "your problem will be back". Anything you add to your gas tank doesn't clean your intake valves, direct injection doesn't spray cleaners onto the back of the intake valves like port injection. I would schedule a walnut blasting for your intake valves or to at least have a look at them before you do anything else.

 

No entirely blind folded. I peaked with one eye. The car had a service record that came along with the car fax which had some regular maintenance, some brake stuff done and fluids changed. I didn't look in depth trying to find out every detail of it. And as far as the N14 consuming engine oil I haven't witness it yet. I've logged 450 miles on it and have not seen a loss yet, im sure it will soon then. I can see why you wouldn't recommend anyone to by a mini s they are horrible cars. And I know anything added in the gas tank will not clean the valves but it will help the injectors. The car is running fine now I will worry about the walnut blasting when the time comes/issue. Over all its still a great fun little car to drive around and really liking it.

 

Extremely fun to drive!

 

This person was having an issue with P0302 and had replaced the coils, plugs, and wires. Maybe check out the thread here and see if it may have some answers.

 

Sounds to me like you replaced the wrong coils the first time round. I can think of no other explanation unless you were to put the ones you took out back in just to prove the point. If that doesn't do it I would highly recommend that everyone use Techron and 93 octane gas when they get a misfire. Glad to hear you fixed it.

 

After carefully examining everything, the new coils have crappier locking clips and I think I may have not clipped them on tight enough, but after messing with them and making sure they sat right I think I got them on good. As an update I haven't had any issue with it anymore and the car is running great. Im glad it was just those coils.

 

A weak failing coil acts up intermittently and is difficult to pin down because bad gas can also cause misfires. There is tons of other symptoms like carbon deposits on intake valves, combustion chambers causing high cylinder temperatures. Glad you got it worked out.