11 replies to this topic

[bloke]

Hi gang, Long story short my old mini cooper got squashed by transit van whilst I was parked up at the lights, and I now have a very nice Mini John Cooper 1999 LE.

 

After saving up for A fault code reader (T-300+) and appropriate lead to talk to the Min I discovered that the ambient temperature sensor is reading -222°C.

 

Here is a picture of the screen- 

 

So my question is, I know that one of the air temperature sensors is the green one, and attached to the right hand side of the engine, (which I have measured and is approximately 2.2Kohms), is this the faulty temperature sensor above, or is there another one I should be looking for? I can't seem to find mention of more than one air temperature sensor.

 

Thanks in advance, Bloke.

 

PS, on a side note one of the fault codes says that the oil temperature sensor is reading low, is this also a negative temperature coefficient sensor and has anyone actually been able to find one for sale, (except on eBay, where they are probably faulty as well.)

[fattail95]

There is no ambient air temperature sensor as far as I'm aware - certainly when I used the correct tool for my MPi (SP ACR4), no ambient air temp sensor was shown, and there sure isn't one in the engine.

[bloke]

Okeydokey, that's a relief. I guess it must be something used on one of the other rovers in the range that use MEMS2j

 

Just the oil temperature sensor sort out now. Has anyone tried to take one apart?

[fattail95]

Okeydokey, that's a relief. I guess it must be something used on one of the other rovers in the range that use MEMS2j

 

Just the oil temperature sensor sort out now. Has anyone tried to take one apart?

 

With regards to the oil temp sensor, I'm sure the ECU doesn't use it for calculating any fuel values. It is put in the block solely for the purpose of the oil temp gauge in sportspacks. So even if it doesn't work, it wont cause any harm at all.

[bloke]

With regards to the oil temp sensor, I'm sure the ECU doesn't use it for calculating any fuel values. It is put in the block solely for the purpose of the oil temp gauge in sportspacks. So even if it doesn't work, it wont cause any harm at all.

 

 

Cool, in that case, I can ignore it for a little while, I'd still like to get the gauge working. I might have to drill and tap an adapter, and fit a sender from another company. 

I wonder when the error code is coming from, oh well, as long as it's not mucking up the fuelling. 

 

Many thanks for the replies fattail95. Happy Mini motoring.

[FlyingScot]

Okeydokey, that's a relief. I guess it must be something used on one of the other rovers in the range that use MEMS2j

Correct. It has no meaning on the mini setup.

FS

[fattail95]

 

With regards to the oil temp sensor, I'm sure the ECU doesn't use it for calculating any fuel values. It is put in the block solely for the purpose of the oil temp gauge in sportspacks. So even if it doesn't work, it wont cause any harm at all.

 

 

Cool, in that case, I can ignore it for a little while, I'd still like to get the gauge working. I might have to drill and tap an adapter, and fit a sender from another company. 

I wonder when the error code is coming from, oh well, as long as it's not mucking up the fuelling. 

 

Many thanks for the replies fattail95. Happy Mini motoring.

 

 

That can work. However (as I'm sure you know) you'll need to check that the varying resistance of the new switch is the same as that of the one of your current one, otherwise you could get some weiiiirrd readings!

[tom1]

I also have 

 

5   Ambient air temperature short to ground

25  Ambient air temperature circuit

13 Oil temperature sensor circuit voltage too high

23  Oil temperature sensor circuit

 

but mine seems to have a fault. At low rev's when you put your foot down it seems to hesitate as if it unhappy. It had new plugs at the start of the year. It just fail it's MOT this week on emissions.So I have tried a new coil pack and leads, but it is still hesitating. It's like you are in the wrong gear.

[bloke]

I also have 

 

5   Ambient air temperature short to ground

25  Ambient air temperature circuit

13 Oil temperature sensor circuit voltage too high

23  Oil temperature sensor circuit

 

but mine seems to have a fault. At low rev's when you put your foot down it seems to hesitate as if it unhappy. It had new plugs at the start of the year. It just fail it's MOT this week on emissions.So I have tried a new coil pack and leads, but it is still hesitating. It's like you are in the wrong gear.

 

Hmm, it sounds similar to something I had earlier with the mini when I first got it, had to change the throttle position sensor, made all the world of difference. You can check using the code reader, if you look carefully, when you push the accelerator pedal the reading should go up slowly, if it jerks up-and-down, then it's faulty. 

 

As mentioned in other threads, it's always worth checking there is no air leaks in any of the system and both of the temperature sensors,(air Inlet, and coolant temperature) this can lead to very rough idle, and I a multiple of other problems as well. 

 

On a side note, I found that the air filter that was fitted to the car, when I got it, was a poor quality one, so I fitted a K&N filter, and this improved the throttle response from idle, considerably. 

 

I hope this might help you with your problem. 

 

On yet another side note, I have ordered up some senders from various MG and Jaguar cars, which purport to be approximately the correct temperature range for the situation I'm looking for. I will probably need to drill and tap my own adapter to get these to fit, however checking on the resistance required for the gauge in the dashboard things look interesting. Will keep everybody updated as to what I find and the part numbers that allow the use of these temperature gauges on the dashboard again. 

 

All the best from Bloke.

[bottledfish]

Hi all,

 

I have exactly the same problem with my 2000 mini cooper. Failed its MOT, so garage connected to diagnostics machine and it came up with fault with ambient air sensor reading of -212 degrees C. However cannot find any such sensor, does it even exist on the car?

Because the temp is so low, its putting more fuel in causing the car to be running rich. If the sensor doesn't exist on the car, how did rover get the car to run properly without it? or is there something else causing this problem on the mini?

 

I am at a loss, help desperately needed.

[FlyingScot]

As above it doesn't have any meaning on a mini. I have moved your post to this section so you have your own thread.

FS

[tom1]

Turns out mine was a faulty oxygen/lambda sensor and an air leak past one of the injectors. Two for the price of one, always more fun to find.