Runs normally until it gets to temperature

[Nehemy]

I have a 2.3 bmw z3, when I use it in cold temperatures it runs normally it has plenty of power throughout all the rpms, but when it gets to temperature it only picks up quickly when it gets to 3000rpms, and is really slow in 1-2 thousand rpms. I’ve changed the maf sensor and it still does that, to be fair it was a cheap one. The radiator has a leak because of the drain plug, so it’s been running with water instead of coolant so I was thinking that would be the reason. I haven’t been driving it because I am waiting on to fix the leak and put proper coolant.

 

[ExMX5owner]

I have a 2.3 bmw z3, when I use it in cold temperatures it runs normally it has plenty of power throughout all the rpms, but when it gets to temperature it only picks up quickly when it gets to 3000rpms, and is really slow in 1-2 thousand rpms. I’ve changed the maf sensor and it still does that, to be fair it was a cheap one. The radiator has a leak because of the drain plug, so it’s been running with water instead of coolant so I was thinking that would be the reason. I haven’t been driving it because I am waiting on to fix the leak and put proper coolant.

Have you put a code reader over it ?...

 

[Nehemy]

Yes I put the code reader over it and says the I need to replace the Maf sensor. But I think the new one I got does not work, because when I unplug the maf sensor the car still keeps running

 

[ExMX5owner]

What sort of code reader are you using ?... I suspect you still have a vac leak.. Even a cheap MAF should last for a day or two, , more info will help the members that know more than I do, help in diagnosing the issue or issues..

 

[Nehemy]

It was in the auto parts that l got my codes from.
Here is a picture of the codes

 

[Pond]

Yes I put the code reader over it and says the I need to replace the Maf sensor. But I think the new one I got does not work, because when I unplug the maf sensor the car still keeps running

I am pretty sure if you disconnect the MAF sensor, the car will just run on a 'default' combustion setting.

 

[Nehemy]

That happens if I start it while it’s disconnected in the first place, but if I disconnect it while it’s running and it keeps running that means it was not even using the mad sensor

 

[IanA]

I am pretty sure if you disconnect the MAF sensor, the car will just run on a 'default' combustion setting.

Correct- I have had to do that a few times. My MAFs that have gone bad allow the engine to start but not continue running. Disconnecting them uses the default settings. Probably would not pass the UK MOT emissions tests though.

 

[GZed]

Correct- I have had to do that a few times. My MAFs that have gone bad allow the engine to start but not continue running. Disconnecting them uses the default settings. Probably would not pass the UK MOT emissions tests though.

Hi Ian, I have exactly this problem. Engine starts then immediately dies. How easy is it to locate & disconnect the MAF sensors? What do they even look like? ( 2.8 TU engine if that helps)

 

[IanA]

It's the unit adjacent to the air filter between it and the throttle body. Just pull the plug and the engine should run.

Check out the link to see what it looks like. There are hose clips either side of the MAF body so it's really easy to swap out.

MASS AIR FLOW METER SENSOR - BMW E46 320 323 325 328 Ci/i E39 520 523 525 528 i | eBay

MASS AIR FLOW METER SENSOR - BMW E46 320 323 325 328 Ci/i E39 520 523 525 528 i.

www.ebay.co.uk

 

[Pond]

It's the unit adjacent to the air filter between it and the throttle body. Just pull the plug and the engine should run.

Check out the link to see what it looks like. There are hose clips either side of the MAF body so it's really easy to swap out.

MASS AIR FLOW METER SENSOR - BMW E46 320 323 325 328 Ci/i E39 520 523 525 528 i | eBay

MASS AIR FLOW METER SENSOR - BMW E46 320 323 325 328 Ci/i E39 520 523 525 528 i.

www.ebay.co.uk

Indeed. Probably the easiest access part of any BMW I have ever seen (certainly on the M54).

 

[Pond]

using the mad sensor

Typo, or truth? Could be either TBH.

 

[Delk]

If you need to change the crank position sensor its a pig of a job.

 

[colb]

Only use oem Mafs either Bosch or Seimens brands, cheap ones rarely work or last long, been there and done that. My symptoms were poor power, it was like the car was being held back. Cheap Maf didn't fix it but oem from BMW at extortionate price cured it immediately.