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Stock Problems/IssuesDiscussions related to warranty related issues and repairs, or other problems with the OEM parts and software for MINI Cooper (R50), Cabrio (R52), and Cooper S (R53) MINIs.
So I’m brand new to these cars and don’t know much about them. I just bought a 2004 Mini and I’ve had nothing but problems with it. I like the car though. On the freeway the other day it all of a sudden lost power began running very rough. I pulled over and had it towed home. It tested a few things and found cylinder 3 not firing. My buddy came over and pulled codes on it. Apparently cylinder 1 and 3 have a random misfire and show low circuit voltage. I replaced the coil, wires and plugs but this didn’t help. Any help or direction would be much appreciated. Thanks
Allot of times the 2303 means the coil is bad. How many miles on the car? Assume you have not changed the coil since you purchased?
160k miles. I replaced the coil, wires and plugs. The coil that came off was super clean and looked new. I’m suspicious this isn’t a new problem to the car. But I don’t know how the guy would have band-aided the problem to sell it either.
Car been driven in winter conditions? If yes it will take some time but I would remove the air cleaner and the ECU, then turn the fuse box over and loosen/lube/tighten all the screws on the fuses they you see when you turn the fuse box over. Also check the ground strap to the engine and the ground strap that is on the fire wall, to the far right of the ECU. You will see it when you have the ECU out and the fuse box turned over.
Car been driven in winter conditions? If yes it will take some time but I would remove the air cleaner and the ECU, then turn the fuse box over and loosen/lube/tighten all the screws on the fuses they you see when you turn the fuse box over. Also check the ground strap to the engine and the ground strap that is on the fire wall, to the far right of the ECU. You will see it when you have the ECU out and the fuse box turned over.
Ok. I’ll give that a shot and report back. Thanks for the direction.
Car been driven in winter conditions? If yes it will take some time but I would remove the air cleaner and the ECU, then turn the fuse box over and loosen/lube/tighten all the screws on the fuses they you see when you turn the fuse box over. Also check the ground strap to the engine and the ground strap that is on the fire wall, to the far right of the ECU. You will see it when you have the ECU out and the fuse box turned over.
So I have all that out. There aren’t any screws on the bottom of the fuse box. Only plugs. The only thing I can find resembling a ground strap is a cable and isn’t really on the firewall. It’s more on the side of the shock tower.
Car been driven in winter conditions? If yes it will take some time but I would remove the air cleaner and the ECU, then turn the fuse box over and loosen/lube/tighten all the screws on the fuses they you see when you turn the fuse box over. Also check the ground strap to the engine and the ground strap that is on the fire wall, to the far right of the ECU. You will see it when you have the ECU out and the fuse box turned over.
Nevermind. I’m a *******. I didn’t notice the 2nd cover to remove. They’re weren’t very tight but not loose either. Everything was clean so I tightened them down a little. Putting it back together now. We’ll see what happens.
Does the bottom look like this? If yes, the screws I refer to hold the FL fuses in place. Be sure those screws are not corroded and are also tight. You should also check that any "plug is tight and the wires are all set (not able to be plucked out). Yes, you are correct the ground I mentioned is not on the fire wall but just infront of it next to the shock tower. You cannot see it with the ECU in place.
Does the bottom look like this? If yes, the screws I refer to hold the FL fuses in place. Be sure those screws are not corroded and are also tight. You should also check that any "plug is tight and the wires are all set (not able to be plucked out). Yes, you are correct the ground I mentioned is not on the fire wall but just infront of it next to the shock tower. You cannot see it with the ECU in place.
Yes. Those are the screws I tightened. There was zero corrosion. I removed the ground strap at the shock tower, cleaned it and reinstalled. I have not gotten to the engine block side of it yet. It got cold and dark. I’ll look at that tomorrow. The car is running 80-90% better though.
The ECU will shut off injector to specific cylinder if it detects excessive detonation or no ignition (bangs) with it. One of the reasons is to protect the cat. Often people start to replace/swap injector, spark plug, cable, and coil pack and fail to fix the symptom. What you should know is the ECU is far from perfect in this self diagnostics. The fault codes should always be used with a big grain of salt - just clues to find the real cause.
The ECU will shut off injector to specific cylinder if it detects excessive detonation or no ignition (bangs) with it. One of the reasons is to protect the cat. Often people start to replace/swap injector, spark plug, cable, and coil pack and fail to fix the symptom. What you should know is the ECU is far from perfect in this self diagnostics. The fault codes should always be used with a big grain of salt - just clues to find the real cause.
So I pulled the plugs. 1,2 and 4 look normal, maybe a little rich. #3 was 100% clean and shiny. I’m starting to think that injector is either not opening or stuck open and washing the cylinder. That low coil voltage code confuses me though. Grain of salt or not. Should I put an ECU in it first or an injector? Is a new ECU plug and play or no?
The ECU will shut off injector to specific cylinder if it detects excessive detonation or no ignition (bangs) with it. One of the reasons is to protect the cat. Often people start to replace/swap injector, spark plug, cable, and coil pack and fail to fix the symptom. What you should know is the ECU is far from perfect in this self diagnostics. The fault codes should always be used with a big grain of salt - just clues to find the real cause.
I haven’t done a compression test yet either. Maybe start with that?
The ECU is looking for outputs from the various sensors and unless a person is able to read those outputs and understand them, you are basically throwing darts blindfolded.
Try a dollar bill test, costs you nothing and will eliminate a burnt valve from the equation. If you have flutter, it is not that the plug is not firing, it is that the exhaust valve is burnt.
