Hello everyone,

I recently purchased a 03 Mini S and was super happy with it. I test drove it and it ran perfect. I bought it and drove about 70 miles with no problems at all! Ran like a top! But after I dropped $600 on registration and plates, bam! Here comes the problem.

I live in Mass (COAST GUARD) and was driving to the ferry (1.5 miles away) and it started to run rough. Just a little at first. I didn't get a chance to warm it up si I figured it was cold. After I got to park the Check Engine Light (CEL) came on. FML.

I got off work and came back to the car started it and it was running like normal. After about a quarter mile the car started to run rough and the CEL came back on. I got to a light and it stalled. I got it back home and ran my OBD code reader with the P2300 "Circuit Low" code showing. It has an MSD on it so I figured it **** the Bed. (Sorry for the language) I picked up a new coil and threw it in and started it up. Rough. It was also hard to start. The revs surged about 500 RPM when idling.

I thought it may be a plug so i checked those and there fine. Same with the wires. Every time i would tweak something it was still the same. This leads me to believe it's electrical. (GREAT)

I check the F20 (Fuel) fuse and it was good. Same with all the other fuses that could effect this.

Does anyone have any idea what it could be? I'm a decent mechanic, but not familiar with MINI. Could it be a certain wire or the ECU? Has anyone else had this problem?

In conclusion, MINI is not being my friend. I love this car and want it to freaking work!!! Below are some mods the previous owner did to it.

Alta Intake
Alta Pulley
MSD ignition
Milltek Exhaust

Thank you for the help! I want to be a MINI maniac, but its hard to when you can even drive the car...

 

I was also thinking it could be the fuel rail? No idea.

 

What kind of gas are you using? Only the top tier premiums are recommended. Just starting with the basics, but if you put crap gas, that might run rough, especially since it ran well for a while.

Did you look at the plugs yet?

No matter what it ends up being, you have to rule out all basics.

 

Quality fuel would be a first thing to try.
Maybe get some octane booster for fuel you have in tank.
I would check fuel filter also.

 

I checked the plugs and just bought it, so I havent put gas in it yet. Thats a good idea though. I'll have to take a look at the fuel filter too. Got to find it first! LOL. Thanks!

 

https://www.northamericanmotoring.co...placement.html

Here is a very good thread for fuel filter change out.

 

Pull and inspect the plugs, you might be surprised what you discover. Here is the fuel filter replacement info.
https://www.northamericanmotoring.co...hange-mcs.html

Way has right spark plugs for your car and he is a great guy too.
http://www.waymotorworks.com

 

Sounds alot like bad gas. If you have checked plugs, wires and fuel filter, gas is next on the list. Minis are great, but they can be tempermental little buggers. Be patient, it will get better.

 

UPDATE: So I put gas and cleaners and de-watering additives with no luck. So i figured I'd try the Poor Mans Spark test on it.

I started the car and pulled wires from the coil. I pulled #4 and nothing! Didn't change the idle at all. Pull #3 and "Chug chug chug". There was a difference. I changed the wires from 3 to 4 and it did the same thing.

What I don't get is that i bought a new one and it was the same. I'm thinking maybe I didn't hook it up right? I think I'll go buy another one and check.

So my question is, if its not sparking on #4 and its not the wires, plugs or ignition, what the heck could it be? Would the ECU have something to do with it? Maybe I got a faulty ignition from the parts store. Another thing is if the ECU was jacked, wouldn't it shut down the whole thing and not just #4 from sparking? Beats the Hell out of me...

 

The stock Mini Coil module has a very common problem where #3 or 4 terminal gets corroded. I'm not sure why but mines was replaced because of it. I got the Screaming Demon coil from Way Motors. It has brass terminals so it should prevent future corosion. I would also replace the wires at the same time, if there was any corrosion it will also be on the wire plugs.

 

Lukeqotsa, here is a "poor man" plug tester.

1) Remove #4 plug wire from spark plug only
2) Insert a "working" spare spark plug into the #4 plug end
3) Using a suitable wire ground the spark plug body to the chassis or engine
4) Start the engine
5) You should see be able to see the spark jumping the gap.
6) If it is sparking then I would check the #4 plug that is in the motor.
7) If no sparking the trouble is up stream

I once got a bad brand new plug out of the box and used this method to test it.

Hope this help

 

Hope you find the problem and it's not expensive.
Fellow 'Coastie" here, 69-73, Base Miami Beach SAR, Air Station Miami SAR

 

Don't forget you have not found the issue just yet. It may be sparking and the injector may be bad. You have to look at the plug that is in #4 now and see if it is soaked with gas before you go and replace anything.

 

+1 on the coil pack. I have a Screamin Demon coil as well. I also have the stock coil pack (I believe). I will send it to you if you want it.

 

Thanks for all the help everyone. Here is what I got going on now.

I got a new coil and same idle. I pulled #4 while running and nothing. I also pulled #1 (same timing) and nothing. This leads me to believe its the wire or the ECU. (*****)

Does anyone have experience with the wiring or ECU? I looked at the wires and the disappear into oblivion. I'm not the best with electronics at all.

I'll keep you posted. Thanks!

 

Right on!

 

It is unlikely that the ignition system will send a spark to only cylinders 2 & 3. Check that you are getting a spark on all plugs. If you are getting sparks on all 4 then it must be the fuel delivery. I would check that the 4 fuel injectors are connected correctly.

 

The Mini runs wasted spark, two plugs firing at a time, one during a compression stroke and and another one during an exhaust stroke. That is why there are only 3 wires going to the coil, 1 for +12v and two grounds to fire it.

As an example (I dont know the firing order off the top of my head), if you arent getting any change when pulling one and four but you get stuff pulling 2 and 3 then that would suggest either a whole side of the coil is fried or one of the leads from the ECU isnt talking to the coil right.

Have you actually stuck a spark plug in wires one and four and grounded it to see if it is firing? Pulling plugs would give the same results as what you experiencing if you were getting no fuel in those cylinders either. Do this before anything else, that way there is no question when it comes to ignition.

After that I would check and make sure you are getting fuel, that would give the same issue. Fuel without ignition would trigger misfire codes I would think.

As far as I know the MINI uses ignitors built into the ECU (converts logic signal from ECU to something that can fire a coil). One of those could have died, though I have never heard of a problem being traced back to that specific area (it would be hard to do so).

It is possible to fry an ignitor if you coil sends to much juice through them. That was an issue with a particular ECU for FSAE cars when combined with non motorcycle coils.


Here is a thread with the same code:

https://www.northamericanmotoring.co...300-p2303.html

 

UPDATE: So after taking it to a BMW repair guy, he deemed it was the ECU. FML. 1215.59 plus tax and labor. Can only be done by MINI.

I also found out you can't go to a junk yard or buy one off eBay. Why do you ask? The rolling code won't match and won't let the car start. So it has to be programed by MINI.

A used one programmed at MINI? NOPE! They will only program the original or a nice new one for the price above. Holy Hell. I'm glad I got a decent price on the car...

 

Sorry to hear about your ECU, but at least I can give you a little confidence that replacing it should correct your problem. The day my ECU failed, it decided to do so at a large intersection, requiring me to find a good samaritan to help me push my car off the road. After I let it sit for a period, I managed to start it right up and drive it straight to my mechanic's shop. After spending several hours diagnosing the issue, he narrowed the problem down to the ECU and as you already know, my wallet became $1200+ lighter. The good news is I haven't had a problem since and it's been almost two years now.

GotMINI

 

I would suggest dumping the MSD coil for a stock one and having the dealer check your wiring harness condition as well.

 

UPDATE: Got a call back from MINI. They said due to the aftermarket coil being cracked, it blew the ECU. Neat. I don't feel to retarded, I bought it that way! Oh well, Its going to be about $2200 to fix. Nice!

 

Ill never put an aftermarket coil on a car with an ECU! F that!