Hey All!

I hope I can explain this right, even though I do not know the name of the thing I am trying to identify (which also makes searching problematic, though I did try...).

The 5 Speed tranny on our 2002 Mini replaced. After putting it all mostly back together, there is a 2-wire connector that we cannot identify what it is or where it plugs in.

There is a large connector that plugs into the ECU. (I believe that is called the "Basic Control Unit DME ECU Wire 39", based on my google searches.)

As you follow the wires connected to the ECU down maybe 6 inches from the connector, there are 2 wires that "branch" out of the bunch of wires. I believe it is a red and a black wire - with an odd shaped connector at the end.

On the attached image, the part I am trying to identify is in the lower left of the picture, slightly out of focus. The connector is almost rectangular, but with some notches in the corner.

So after getting the transmission back in, we cannot figure out what those wires connect into. We looked all around the fuse box area, and everywhere within reach of the wires and found nothing!

I am sure we are missing something really obvious, but I am stumped. Can anyone identify it from my description or the attached image? If so, where do I plug it???

I suspect it plugs into some sensor, because the check engine light now comes on, and it is not running well (according to the mechanic... we haven't driven it yet.



Thanks so much!
Cervantes
I am trying to ID the wire connector that is in the lower left corner, out of focus (sorry). It runs along the wires that connect to the ECU connector (top of the screen.)

 

Hmm.. Should I have put this under Stock Problems/Issues? If so, is there a way I can move it, or do I need to delete and re-do it?

Let me know if this needs to be changed.

Thanks,
Cervantes

 

I will move it for you

 

Maybe the obdc codes could help?

 

r3Coop, thanks for moving the thread! I appreciate it.

VelvetFoot, I will get those codes when I get home from work tonight.

The strange thing on this connector.... It is a short wire, so there is not a lot area to cover, but we still cannot figure out where it plugs in. It has to be something *right there!*

More info coming soon.

THANKS,
Cervantes

 

You have any salvage yards nearby with your model? You might be able to see the wire termination.

There should be a male end for that female end to go over. Did you turn the fuse box over and look for a plug?

 

Ok, finally got the mini back home and had a chance to look at it.

The error code is P0301 - Misfire # 1 cylinder... Not sure if this mystery wire could be related to the problem or not. I guess if it ties in with the computer, that could make sense.

Plugs seem good. Resistance on the cool packs seem right. Sure on all 4. Still runs rough and the error code.

And ideas on the wires? Or hints???

Thanks,
Cervantes

 

Which connection is this on? bigger or littler ecu plug? Also a better picture of your mystery wire would be helpful. Where it's at on the loom, what the insulation is like... Right now we can really only tell that it's a 2-pin connector.

 

What is that line that goes from the ECU into the air box? If I did not know better I would think the car had a JCW air box on it. The plug may be the connection to the air box solenoid, I will look in the morning.

 

Looks like the wiring connector for the battery disconnect switch that was installed at the factory when the shipped the cars over. Then when we got them at the dealer we would remove the switch during the PDI. That connector is just part that was built into the wiring that would just be left like that.

I actually have some of the original electronic battery disconnect switches if anyone ever wanted to add it back. LOL

 

P0301 could mean a valve is bad. How many miles on the engine?

 

Ok, attached is a better picture.

​​​​​​Milage is about 100,000. I did a (cold) compression check and they were low-ish but even. I suspect the low part was because the engine was not warmed up.

We swapped the injectors and reset the codes... No change. Same code, still on #1.

I'm thinking I will replace the coil pack for #1 and go from there.

Does the wire look like the one that is not used one they are off the boat?

I've had a hard time getting to this one (work has been busy) but need to get it worked out soon! We are short on cars!
Thanks for the help!!
Cervantes

 

My compression numbers were around 105 and pretty even across the board and I had 4 cracks. I also had no CEL. Eliminate bad valve with the dollar bill test.

 

Wow, that dollar bill test is a new one to me, but I googled it, and that makes sense. I will try that as soon as possible.

Thanks,
Cervantes

 

Was brand new to me, too. Best part is it's free and only takes about 10 seconds including time to turn the car on! Good luck!

 

Added the image as it was not showing up.
Well, I think I have a problem. I put a card in front of the exhaust... Mostly it blew out, but when I put a corner of the card in the exhaust a bit, it seemed to suck in slightly between blowing out.

The strange thing is that it ran great until we replaced the tranny... Ran great to the shop, then ran rough on the way home. Nothing else changed between, so I didn't expect it to be a valve!

Ok, so is the dollar test conclusive, or is there a next step before pulling is all apart?

Is it possible that carbon build up could cause that test to gain? Maybe some Seafoam (and a prayer) be in order? Thoughts.

What a day! Thanks for the help!!!

Cervantes

 

Before I did anything I'd use a slip of paper or a dollar - something more flexible than a card. Eliminate any variable there and get a more definitive test result.

What the test actually shows is that at least one exhaust valve isn't sealing properly. It's entirely possible it's due to carbon build up on the seats. There's no harm in my eyes in doing a full run of seafoam and giving it the old italian tune up.

While you're at the auto parts store, rent a compression tester and give that a shot, too, just so you have a fuller picture of what's going on. Will only take about 10 minutes after warm up and won't cost a thing.

 

Thanks! I will pick up a better compression tester, and do a real compression test on it this weekend, and see how that looks. I'll also re-do the Dollar Test with something more flexible.

Besides that, I'll run some Seafoam through. Maybe I'll get lucky and it will just be carbon build up and maybe that will clean it.

 

That is the vent for the battery, and thats the battery box, I believe on a R50

 

Hey all!

Sorry there is so much time between my replies! I am having a hard time getting to the car after work!


Compression Test Results:
OK, I got a decent compression tester and all 4 cylinders were in the 160 range, give or take just a few pounds... So I am less convinced it is a valve.

Next Steps
My plan from here is to replace the Coil Pack. Also, I got some Sea Foam spray that is formulated for carbon buildup on the valves. It looks like you spray it in while running... I will give that a try to, in case there is a carbon issue.

Wires?
I'm still not clear on what those wires go to.

Am I understanding right: There was a cutoff switch from the factory, that was removed by the dealer on arrival? So those wires don't need to go anywhere? Is that correct? If so, that is cool (Though I won't tell my son as he spend a few hours trying to figure out where they plus in! ;-)

Thanks all,
Cervantes

 

In red:

 

Ok, here is the update...

1. Put in a new coil pack. No change.
2. Replaced the soak plug cables. No change.

So I am again at a loss. We have eliminated everything I can think of...
- compression is solid.
- swapping injectors did not change the code, do that seems ok.
- plug good
- coil / spark plugs cables no change.

I ask out of ideas. She still sounds rough and had a misfire on #1.

The coil was only on for a few minutes... Is it possible the computer might take longer to readjust to a good coil?

Any ideas would be so helpful.

Thanks,
Cervantes

 

Have you verify there is indeed spark generated by the coil pack for cylinder #1? Typically the modern car two cylinders share one common low voltage drive pulse. Your problem may be with the low voltage drive pulse to the coil pack - since you already replace the coil pack.

Be careful when carrying out the visual spark test with an old sparkplug. Have the case grounded securely and make sure you are not exposed to the thousands of volts.

Lastly I didn't read carefully to see if you swapped the spark plug on #1.

 

If you have good compression, it has to either be fuel or spark. You eliminated part of the fuel by swapping injectors so that's good. I'd double check any and all fuel lines, as well. I don't remember if you did that already. You also eliminated part of the spark potential with the new coil and wires. I'd double check that the fuel harness is making a good connection with injector 1 as well.

 

I concur that it is either ignition or fuel to #1. Since the problem occurred right after the transmission work, I would first check if the tech somehow unintentionally cause an electrical connection to come loose or half loose (like #1 injector cable harness), or damaging say a wire in the engine harness. If you are methodical, it should not be that hard to track down the problem.