Weirdness. But this is the third year in a row my Mini has acted up during the 'wet' season here in Guam, but never before with this symptom. Last 2 years it has been the Body Module where-as the windows and dash lights don't respond properly.

Sunday morning, I park my car right before the storm. Monday afternoon I go to start it, and get a VERY rough idle followed by a stall. Restart results in a rough idle, and no response when I push in the accellerator.

Tuesday afternoon after work, same indication, no stalling.

Wednesday afternoon, same.

Thursday afternoon. No more rough idle, but still no response when pushing in the accellerator.

I don't have a code scanner, so I've not looked at that yet. BMW here charges $110-120 an hour for labor, so I want to do my best to resolve on my own before that last resort. Help.

 

Sounds like you might have a loose throttle body control wiring connection.

This is the mutli-plug on the throttle body. You can see it just behind the radiator.

 

Does it seem moisture related? If so, may want to replace plug wires, check all drians in the cowl to make sure they are clear, check the covers to the ECU and engine fusebox, make sure they are sealed.

 

A good code scanner cost less than 1 hour of BMW labor.
I have no idea what kind of auto parts places are in Guam but if there's an auto zone you could buy or borrow a scanner.

Feel around on the floor near the gas peddle - damp or wet & check connection on the peddle itself.

 

Sounds like a wet Control Unit... I had the same issue.. the cover wasnt on correctly and it the plugs to the ecu got corroded had to tow it and rplace the ecu $2,300.00 WOW!! runs great though :-)

 

+1 does sound like moisture wish i knew more about the workings of these . i'd say spray all connectors (insideand out) and ecu itself with wd40. do one at a time till issue goes away . this will tell you which is the culprit . you can then pull that component apart and clean it .

 

Ouch. My warranty ran out 2-3 months ago. :( And I'm sure they'll charge me more than that here. They want like $42 for an oil filter.

 

Well, I brought my toolboxes to my work parking lot yesterday to see what I could see. Results:

* 3 blown fuses found. Cig Lighter, Radio, and parking distance equipment (not installed).
* Dirt/corrosion between chip and ECU. Corrosion between pins on ECU, may have caused a short/ground damaging ECU.
* Seating of the connector on the throttle body was good.

So I cleaned the connectors with some cotton swabs, removed as much vertigre and corrosion as I could. Removed the chip from the equation by removing it from the ECU. Fixed all the blown fuses. Same symptoms. Car starts and runs fine, no response to the gas pedal.

AutoEnginuity software on order, and getting a price quote on an ECU in case I need to get it shipped here. Since the warranty is already kaput, I'd prefer to only see the on-island dealer as an absolute resort. I think in the 2.5 years I've been here, they've only sold 30-40 Minis. I don't think they're experienced on working on them... Plus the $110/hr labor charge. Last resort.

 

try an eraser on a #2 pencil on the contacts for the ecu. also be careful for static discharge (no carpet) spray the insides of the connectors with wd 40 . wd stands for water displacement . wont harm a thing. check fuses again as you may have a direct short and blew on again.

 

I don't know that I can clean with an eraser, as the pins are VERY close together. Will need to see if I can find something smaller. Used medical cotton swabs with most of the cotton removed, and could stick the swab head (1mm across) vertically between 4 pins, but theres not enough room between 2 pins.

Didn't have WD40 on hand when I went, but I'll give that a try the next go-round.

 

sry i'm thinkin' board try some contact cleaner; but now i think about it the pins should be pretty good yes? so if not a fuse you gotta check output outa the pedal to the ecu and if it go in with no ecu responce then yup prolly ecu . sucks

 

Right, but I have to figure out how to check that value and where to check for it if I can even do it. I may have to wait on AE to show up to see if the computer sees an input from the pedal.

 

Without a code there's no way to diag the problem, without substitution method.
The peddle is the first place to look. Here in New England wet snow can melt & re-freez inside the car ( if you drive in the winter ). There IS a strong possibility the plug on the peddle or the unit itself is your issue.
I have a reader I could mail to you so we can see what the SEL is. It would take some time to get there but........
There is no evidence that the ECU is the problem.....YET. Lets hope for the best. Simple = good.

 

I found a website www.eautorepair.net that has service manuals, repair manuals and wiring diagrams for mini coopers up to 2008. they don't have manuals for 2009, yet The annual subscription cost is about $29.00 a year. You can download the manuals or wiring diagrams as often as you want. With that you could locate the connectorsand componentsto see if they are contaminated. These are Mini repair, service, wiring manuals and service bulletins. Something good to have since your mini is out of warranty. That way if you need to trouble-shoot or repair the car you will have factory manuals. If nothing else it will give you some idea as to what's causing the problem before taking the car to the shop.

 

AutoEnginuity will be my reader and gas pedal sensor checker, and is on order. I looked at the pedal assembly under the dash and didn't want to try to crack it open by hand to see whats what. I'll refer to my Haynes manual to see if it says anything about the pedal. I doubt it. May need the Bentley manual.

Thanks for the reference AirMikeMech. Hopefully I won't need it because I'm pessimistic about subscription services that may not help.

Also inhibiting continual troubleshooting is my very active work schedule, and the fact that my car is out in a parking lot, not at home. May end up towing it though. Boo.

 

Well, car has sat in 'mostly' dry conditions for the last 2 days. Tried today and got gas on the first try. Still being cautious, I only drove around the parking lot. I got about 100' before the gas cutout again. I had to 'idle' in reverse to get back into my parking spot.

So now theres a slight change to the symptoms. Other than the freak 45 seconds I drove it around... If I start the R53 with my foot down, it will rev up to redline, then drops to idle. If I start with no pedal, it starts and idles normal. Regardless of how it's started, the gas pedal gives no response after about the first 1.5 to 2 seconds. I think this indicates it's not a mechanical problem with the pedal... Rather one with the computer disabling or losing the gas input signal.

 

"I think this indicates it's not a mechanical problem with the pedal... Rather one with the computer disabling or losing the gas input signal."

It's all electrical. The only mechanical part of the pedle is the hing.

 

swap the pedal unit with afriends . for diagnostic .

 

Thats going to be a challenge, as I have no Mini friends on Guam. :(

 

Well, it's already friday night here and the dealer doesn't have service or parts support on the weekends. So I'm likely going to have the Mini towed there Monday to have them troubleshoot. Morristown MINI gave me a price quote on an ECU, but specified that it comes unprogrammed so I have NO choice but to go to the dealer regardless of where I get the part. So I might as well have the dealer prove to me it's the ECU. They also said over the phone that they would allow me to acquire the part elsewhere since they don't maintain it in stock. Meh.

Verified the same fault exists today... 10 seconds of gas pedal and then nada but idle.

 

a guy posted a cpl' weeks ago about his car only running at 30 mph or more ,but if it fell below that it would die . turned out his ecu needed to be "aligned" by the stealer . mention this to them and mark your ecu descreatly so you can prove they never even replaced it . serial numbers on it? not a sticker. trust me my uncle did something similar with a toyota dealer. they gave him his money back for a tune up they never did.

 

it gets power, ground and two varying resistors with pedal position. If you power it, then the voltages out go from 0.5-4.5 on one of the outputs, and 0.5-2.5 on the other. But I'm thinking it's not this. The 0.5 volt offsets are to check for shorts to ground and the 5 volt supply, and the two voltages are compared for safety sake. If they don't agree as they should, then I think you get a code.

There are good contact cleaners out there that should take the crud off the pins. Also, if you're REALLY AMBITIOUS, the ECU connectors come apart and you can remove individual pins for cleaning.

I'm actually really surprised at the corrosion. These are pretty good connectors with a seal around the body, and each pin has it's own seal as well at the back for each wire. But then, there are a lot of pins!

Matt

 

Good idea, will do.

If I had a garage and some time, I may attempt it. But my car stays outside 24/7 because I have not a garage... Nor really time to work on my Mini nowadays. And the pins sticking up out of the ECU are REALLY close together...

And I do have a Unichip installed... So it's the unichip harness (which I believe is an OEM harness), not the stock ECU plug, plugged into the top of the ECU. The stock connection which plugs into the unichip was clean, and then the unichip plugs into the ECU which is where the corrosion is. It's not a 'large' amount of corrosion, based on what I'm used to on a 30 year old Navy ship sitting in ~80% humidity daily. I think there's a 50% chance that corrosion on the pins may have contributed, and more than likely it was crud buildup (from corrosion?) sitting on the bottom of the ECU's plug tray that led to a short or ground between pins.

 

Where? I can't figure out how to access the pedal base.

 

Dealer called. Said replacing ECU not necessary, the corrosion on the pins were the culprit. The Batmini is back to 100% and I can pick it up tomorrow.