Hello all!

I'm interested in purchasing a 2006 Mini Cooper S. The vehicle has about 20,000 miles on it, full exhaust, CAI, SC pulley; the usual.

The owner tells me there has been a Service Engine Soon light on the entire time he has owned the car (about 10,000 miles/2 years).

The code is P0130, which I've discovered has been discussed at length multiple times on this forum via searching for a couple hours. There doesn't seem to be a consensus on how to fix it, though...

The seller says the SES light comes on intermittently in various driving conditions. It stays on for a few ignition cycles, then goes off.

The dealer told him they could replace the Pre-Cat O2 sensor, but it probably wouldn't fix the issue.

It seems as though that response is pretty standard. I know about the warranty extension on the sensors, etc.

It also seems that replacing the sensors has worked for some; the code has gone away and stayed away. For others, it has come right back.

I've never bought a car with a SES light on before-but it seems like it many MINIs on the market may be stricken with the same issue.

Is there a solution to get rid of this code? Is it something to worry about long-term?

Any insight is appreciated!

-Will

 

It has everything to do with the full exhaust I believe. I replaced the post cat sensor and it got much better for me. It still happens once and a while, but not that often. Best shot at making it better is to replace the O2 sensors with the exact factory ones since there have been some that had issues with other brands.

 

I guess my issue with the whole situation is I don't understand WHY it throws that specific error.

In theory, the pre-cat O2 in a factory manifold and the pre-cat O2 in aftermarket headers are reading the same thing, in the same position.

Why would the sensor be relaying a low voltage code to the ECU?

Would it stop throwing the code if I put the OEM exhaust on from engine to cat and just ran an aftermarket catback?

It seems that this code has even been thrown for people with no modifications on their cars at all.

This is on the verge of scaring me out of a buying a MINI because I'm afraid even a stock one with low miles will end up with the same issue.

Aren't O2 sensors supposed to be fine for ~100,000 miles? Why are they going bad as low as 20,000?

What gives?

 

Don't let this issue scare you away from a Mini as it's correctable.
As 'HRM' has posted it's most likely the header.
In all probability with only a cat back and the 'OEM' O2 sensors the code should clear and not return.

There have been some posts about aftermarket headers and their incompatibility with O2 sensors.
Some of the vendors have since modified the headers that they first sold as well as incorporating those changes into the new ones.
I think by now all of the vendors have got a handle on the problem.

Also you should know that there has been a problem with the factory O2 sensors and Mini has said they will replace all defective sensors.

Hope this helps...

 

Is this the best way to remedy the situation?:

1) Install OEM Headers/Cat

2) See if code disappears

3) If code remains, have sensors replaced at dealership

What do you think the chances are that this will get the code to go away for good?

I REALLY don't want to be driving around a "nearly new" 20,000 mile car with a Service Engine Soon light on...

 

I think the odds are great it will go away. The CAT (if there is one...you never know) is not as restrictive and the exhaust flows faster, so fast, it may not do the same job the computer is expecting it to do.

Again, my code mostly went away (about once a month it pops up) by changing the post CAT sensor.

 

There is a cat.

ALTA says the header doesn't cause any issues like this and it is completely related to the O2 sensors.

Basically ALL the parts on the car (minus catback) are ALTA. S/C pulley, TMIC, headers/cat, etc.

The dealer has said in the past that the code is due to the "performance" parts on the car that are causing the sensor to read outside the set parameters, that it is fine and not to worry.

Can that be? Are injectors, a larger IC, and a supercharger pulley really making the exhaust so scary that the first O2 sensor can't take the party and throws a code?

"Not worrying about a check engine light scares me, quite frankly.

 

I have an alta full exhaust, I got the codes to almost go away by replacing the O2 sensor after the CAT. It seems more than one person is telling you the same thing. Maybe they are correct? I would replace both sensors with the exact factory replacement and buy a scangauge so you can reset it if/when it pops up again. (It will)[but hopefully a lot less frequently).

Putting on the stock exhaust will make it go away.

 

I have a ScanGauge already, so I'm good to go as far as that is concerned. It's a carryover from my old Subaru.

The owner is getting the O2 sensors replaced at the dealer on Tuesday under the warranty extension through MINI.

When you say "stock exhaust", does that include the engine-back, or would simply replacing the header and cat with a factory unit do the job? The header/cat is the preferable solution.

I just want to say thanks for the help so far, I appreciate it.

 

I'm sure that's what he means. There are NO issues with a cat-back exhaust mated to the factory header as far as codes go.

 

Glad to hear this!

Just to reiterate...

I should not be concerned about a modified MINI should it throw an occasional P0130 once O2s are replaced?

If I wanted to deter the code from even occasionally being thrown, replacing the header/cat with an OEM unit would solve the issue for good.

Yes?

 

Yes, it is the header...

To further complicate (or clarify...which is my intention) the second sensor is sort of like a nanny. It doesn't have much to do with engine management. It just is to make sure the CAT is working...this is the sensor that usually will toss the code. The only thing that happens when this code goes off is the light turns on. However, the first O2 sensor is used by the computer to run properly. This code will effect things.

As long as the first one is good, the second doesn't matter at all.

 

I'm pretty familiar with O2 sensors from my Subaru days, especially the latter O2 sensor and the P0420 Catalyst Inefficiency code (which, as you say, is usually disregarded) on aftermarket downpipes w/ or w/o cats.

My goal is to have no Service Engine Soon lights at all.

It sounds like people have issues with primarily the 1st O2, but also (yet less frequently) w/ the 2nd O2.

Let's hope that the new OEM sensors in both positions will do the trick and extinguish the light!

The dealer has been telling the current owner of the car that it is because of the pulleys, injectors, etc. that the light is on. The "higher performance" is leading to out-of-range readings on the O2s....

I think this is wrong. I've had 400BHP Subarus in the past with no such issues on O2 readings...

Thank you all!

 

Just a bit of added information.

I had the P0130 on my 2006 MC and went through hell with the stupid universal fit Bosch O2 sensors. ***DO NOT BUY THESE!!*** I ordered a Bosch exact fit sensor and it looked the same as the universal but it had the connector on it. The code came back. Again I ordered a Bosch exact fit but this one looked exactly the same as the stock sensor that I took out. I put this new sensor on the upstream and put the exact fit that looked different on the down stream and so far (fingers crossed) the light has yet to come back on.

So I guess the moral to this is: If it does not look the exact same, Don't use it!!