Hello everyone. I have a 2003 MCS with the mods listed below. Recently I was driving and I noticed the car was cutting out under hard acceleration as it got up in the RPM range (about 4-4500 rpm). I tried to get the car to repeat and could do it pretty consistantly. At first I thought it was bad gas, as I had just filled up. At the fill up I had added some Chevron Techtron to the fuel.

I took the car out and was accelerating pretty hard in third and the car did it again, and the check engine light came on. As soon as the light came on, the car was WAY down on power, and it would not develope any boost. I can only describe this as "limp mode".. I go the car home (about a mile), and turned it off and restarted it and it seemed to be back to normal (SC whine and all). I did not take it out again.

Took the car to work the next day, and it seemed fine (boost and all), but I could still get the flutter around 4500 rpm. Plugged in to the OBD port and got P0302 Cylinder #2 Misfire Detected. I checked the Coil for any cracks and sprayed the plug wires while it was running and got no skipping. Reset the Check Engine light.

I got a set of NGK BKR7EQUP plugs today and installed them. Took it out for a drive today and I have BOOST and no flutter / hesitation any more. I will probably replace the coil pack and the wires shortly though, as they have about 35,000 miles on them (and are over 5 years old)...

So, here are some pictures of the NGK Iridiums (BKR7EIX-11) I took out of the car, they had 20,000 miles on them.



This is way they came out of the car. As you are looking at the engine bay. Can anyone tell me which cylinder is #2? How do these plugs look for 20,000 miles? Thanks for all the help.

 

just so you know... spraying the plug wires wont do anything. the test your referring to is spraying brake cleaner or another aerosol flammable material onto intake hoses to check for leaks, the engine will rev when you find one...

 

Not to dispute you or seem like a know it all, but this is a very common easy test to try and spot a bad wire. There are many different ways, but this is an "old school" way of checking... As seen here:

http://www.youtube.com/watch?v=xXAFQa0R9hA

 

the spark plugs in the picture look just about normal. Maybe they were just too hot of heat range and the ECU was detecting knock? Do you live in CA or a place with "91" premium? I killed a spark plug and chipped a exhaust valve due to CA gas/17% pulley/too hot of plug.

 

R53Warrior, thanks. The NGK's pictured are one heat range colder plugs. Here in Vermont, we have 93 octane and it is what I always use. Maybe, there time was just over. The car is running much better with the new NGK's (platinum 4 prong, 1 heat range colder). The upgrades are 15% pulley, Alta CAI, Shark Sofware and Milltek Catback...

 

Don't forget the basics. Check your coil terminals to make sure they are not rusty or corroded. #3 terminal is notorious for corrosion. They clean up easily with STP Carb Spray Cleaner and a shop rag and/or a brass brush. Get some terminal grease and put a little inside the spark plug wire boots (you can get small packets at Autozone for like $1).

Here's what mine looked like last summer:

 

woah, i never knew you could do that. my bad. definitley check your pack, mine wasnt working correctly and caused some problems. i love my new screamin' deamon which i bought used on the marketplace for like 40 bucks.

 

No biggie. You learn something new everyday. If we knew it all, we wouldn't need this place. I am going to check the terminals on the coil pack and clean and put some fresh die-electric grease on them. Probably going to replace the wires, only because they are 5 years old...

 

that you do! try that, and also check that all your plugs are torqued to spec.

 

Several others here on NAM have commented about having spark issues with the Screamin' Demon pack. If you're having erroneous throttle response problems, try putting back in you're OEM one and see if that makes a difference. If I ever do upgrade, it will probably be the MSD design.

 

thank you for my daily dose of learning.

 

Hey not to hijack, although I think this thread is pretty much done. With regards to the coil pack and plug wires. I have an '05 with 60k and the stock coil pack. Two years ago I had a Denso iridium plug blow out on #2 cylinder and had a heli coil put in along with BRISK 4 prong plugs that I got from RMW. I also replaced the wires with another set of OEM ones. I've had a terrible hesitation since then and I can't figure out what it is. So the other day I was playing around with the wires and I noticed that the #2 wire doesn't "click on" to the coil pack. I'm assuming people know what I'm talking about. As you push the wire end onto the coil it usually clicks or snaps onto the coil terminal. Anyone think there is anything to that or am I just throwing ideas out with no direction?

Thanks,
Steve

 

If a spark plug wire is making intermittent contact, that can certainly cause hesitation issues. If it were arcing really bad, the terminal may appear black in color. A cylinder not firing correctly is more obvious on an I4 vs. a V8. You might have also noticed a degredation in your fuel economy.

You can always take a pair of long needle-nose pliers and pinch the two halves of the terminal connector inside the plug wire boot so they will make better contact on the terminal. If the hesitation still exists afterward, the problem might lie somewhere else.

Only other thought that comes to mind is the helicoil is not properly sealing. If that were the case, though, you would see or smell fuel and/or carbon in the plug tube. In addition, I would think the plug boot that goes down the tube would have blown out.

Pull your plugs and inspect them. Normal fuel burn should produce a light to medium brownish-gray color.

 

Good idea with the needle nose pliers. Thanks! I was originally thinking the same thing with the helicoil but also came to the conclusion that there would be some sort of evidence showing. But nothing out of the ordinary and the boot is always properly sealed and pushed down. Then I thought that maybe the helicoil wasn't in the right place and the plug was sitting too high in the chamber but they all measure the same distance. I pulled the plugs out and they are all whitish brown except the helicoil cylinder which was significantly darker colored. Not totally black but quite dark. Obviously something is going on where the fuel being delivered is not being burnt completely but why totally stumps me. No check engine light has ever come on. I think I'm just going to bite the bullet and bring it somewhere to get diagnosed. I'm all out of ideas as to what I can actually test or inspect at my house.

 

#2 is not usually the one that gets carbon buildup on it. Best to bring it in, it could become a larger problem the longer you wait. Please let us know what the outcome is!

 

then you'll be unhappy to hear its been over two years! LOL Granted I haven't driven it as much as I used to since this happened but most likely over 10k miles. I really don't have an excuse. I guess I always wanted to figure it out on my own but this has really just stumped me.

 

So long as the cylinder is firing, you'll just be dealing with some sort of carbon buildup in the cylinder quench area, on the piston top, and in the combustion chamber. There is one way you could possibly compensate. Hotter or colder plugs usually are just to adjust how far the electrode sticks out of the end. Colder usually recesses the plug, so you might be able to compensate by using a hotter plug. As an example, NGK BKR6s are supposed to be stock (although some came with BKR5s; depends on where the MINI was delivered to). BKR7s are a colder plug, which means the electrode is recessed a bit more. Based on your mods in your sig, I would say you're running something like them. You could get a BKR6 or BKR5 and see if the burn is better. If you are running something like Brisk Silver DOR14LGS plugs, try a DOR15LGS to compensate.

 

take the MSD and screamin demon coil packs and throw those POS into the trash We have had more issues with those 2 coil packs than any other mod on the cars

I run the stock coil and plug wires on our 375whp car
I think the proof is in the pudding...........

http://www.youtube.com/watch?v=VlfY_gQfY9I

 

take your coil pack off the car, flip it over............if it's white on the bottom, get a new one. If it's still grey it's probably good
Replace plug wires anyways. If you still have a problem, call me

 

#2 (second from left) is leaner than the others
if you have the shark injector many of the early ones had excessive timing in them, some upwards of 33-36degs final timing............WAYYYYYYYYYYYY too much for a pulley car EVEN ON RACE GAS!!!!!!!!!!!!

 

I knew you quoted 300 HP, but I did not realize you've gotten them to go higher.

 

why mess with stock parts that are more reliable UNLESS you have to?

 

Yeah, I second that theory!!! I blew my ECU messing with rubbish parts that didn't need to be on!!! I'm sorted now though

 

Love that video! Sent the link to my buddy from the Army that lives and breathes BMW!

 

Thanks for the tip Jan. I'm gonna take a peek at that this weekend. I didn't mean to reference you guys with my problem, guess it really was just a plug for you selling Brisks.

Steve