hey guys i got this code - United Bimmer Community

**nhevynopal** · 04-15-2009, 12:14 AM

Its 201 on a 93 bmw 318is. Has anybody gotteen this code

**David Mc** · 04-15-2009, 05:37 AM

Fault Code 201 = Oxygen Sensor Control (M42 & M43 engines)

Big Evil · 04-15-2009, 04:13 PM

Cool, now you have to trace WHY. Could be a bad O2, could be something else causing it. What's the car doing since the code happened?

**nhevynopal** · 04-15-2009, 08:30 PM

mmm the ligth comes on and of specilly when the car is cold then it starts acting funny i press the gas in all the way and it feels like its choking and all of a suden wham take off its a m42 engine

Big Evil · 04-16-2009, 04:29 PM

Do you have a vacuum gauge? start it, check it see what it pulls. May be a clogged cat, could be a simple vacuum leak. Does the car lack power when running warm? How long does it take to run normally (or does it)?

**nhevynopal** · 04-16-2009, 08:06 PM

when it gets hot it runs normal but sometimes i can feel that it chokes a little bit then it keeps runing normal well when the temp gauge reaches the mittle thats when it starts to run normal

Big Evil · 04-19-2009, 09:45 AM

Does sound a bit like an intermittent vac leak, maybe in a component. Once everything warms up it expands and seals. Or a sensor issue and once the car goes into closed loop operation (pcm adjusting fuel trims because its now recognizing the O2 sensor inputs). May need to get the car hooked up to a scanner and see what the computer is seeing when cold (when its having the problem).

**knights** · 02-01-2010, 11:29 AM

Quote:

Originally Posted by nhevynopal

when it gets hot it runs normal but sometimes i can feel that it chokes a little bit then it keeps runing normal well when the temp gauge reaches the mittle thats when it starts to run normal

Hi,Im having the same problem,but mine the lights never light up.Just the feeling of choke when the gear from 2 to 3 then 4...but when engine hot or not ,mine same ..

Fault code same 201!I have find all ways to solve it,change many suspect parts like fuel pump,fuel regulator,fuel filter,fuel line,injector cleaned,air flow sencor change to my spare ones,lamda sencor changed,mannifold valve changed...

But i suspect is the ecu after all..

Hope you had found your ways to solve it,and can share with me..

Not forgetting thanks all for help,if any..

Cheers..

**David Mc** · 02-01-2010, 03:43 PM

201 is definately O2 sensor control. Bear in mind that the temperature sensor sends messages to the DME so that it can set appropriate fuel trim values according to engine temp. (i.e. cold engine = rich mixture, warm engine = lean mixture etc). If the engine temp sensor thinks the engine is cold when it is actually warm, the DME will enrichen the mixture but the O2 sensor will detect that the mix is too rich and attempt to lean it out. In other words, the DME will receive conflicting messages from the O2 and temperature sensors. In light of the effort you have put in up until now, I would tend to bite the bullet and change the temperature sensor (the one on the side of the cylinder head, not the one on the radiator).

**knights** · 02-05-2010, 11:38 PM

Quote:

Originally Posted by David Mc

201 is definately O2 sensor control. Bear in mind that the temperature sensor sends messages to the DME so that it can set appropriate fuel trim values according to engine temp. (i.e. cold engine = rich mixture, warm engine = lean mixture etc). If the engine temp sensor thinks the engine is cold when it is actually warm, the DME will enrichen the mixture but the O2 sensor will detect that the mix is too rich and attempt to lean it out. In other words, the DME will receive conflicting messages from the O2 and temperature sensors. In light of the effort you have put in up until now, I would tend to bite the bullet and change the *temperature sensor (the one on the side of the cylinder head, not the one on the radiator).

Hi ,are u saying that the *temp sensor is the one connect to our meter,engine temp gauge? My gauge is quite normal,its start from zero then when warm up is middle. Or temp gauge is the one connect to radiator?
Thanks..

**David Mc** · 02-06-2010, 04:12 AM

Download the Electrical Troubleshooting Manual for the 1993 318is from here http://www.wedophones.com/Manuals/BM...g%20Manual.pdf .

According to the manual (and OEM parts listing) your car has 2 coolant temperature sensors - one connected to the temperature gauge (component B6232) and the other connected to your DME (component B6236). There is also another temp switch on the top LHS of the radiator for the thermo fan. If B6236 (front RH side of the engine, under the intake manifold) has gone bad, it may not show on your temp gauge, but can signal the DME that the engine is cold.

**knights** · 02-06-2010, 01:08 PM

Quote:

Originally Posted by David Mc

Download the Electrical Troubleshooting Manual for the 1993 318is from here http://www.wedophones.com/Manuals/BM...g%20Manual.pdf .

According to the manual (and OEM parts listing) your car has 2 coolant temperature sensors - one connected to the temperature gauge (component B6232) and the other connected to your DME (component B6236). There is also another temp switch on the top LHS of the radiator for the thermo fan. If B6236 (front RH side of the engine, under the intake manifold) has gone bad, it may not show on your temp gauge, but can signal the DME that the engine is cold.

Wow a BIG thanks for the help! But the electrical manual I need a wire man to help me along

karime302 · 02-07-2010, 07:06 PM

thanks for this nice info

**knights** · 02-08-2010, 01:09 PM

Quote:

Originally Posted by David Mc

Download the Electrical Troubleshooting Manual for the 1993 318is from here http://www.wedophones.com/Manuals/BM...g%20Manual.pdf .

According to the manual (and OEM parts listing) your car has 2 coolant temperature sensors - one connected to the temperature gauge (component B6232) and the other connected to your DME (component B6236). There is also another temp switch on the top LHS of the radiator for the thermo fan. If B6236 (front RH side of the engine, under the intake manifold) has gone bad, it may not show on your temp gauge, but can signal the DME that the engine is cold.

Today I just purchased 2 sensors,hope I got it right!
Since is not costly for both,I think I change it at the same time.

The parts are: 1262 1 747 281 Temp Sensor
& 1362 1 709 966AG Temp Switch

Will try out and see whats the outcome..

**karimMsalama** · 02-09-2010, 02:20 PM

very nice info thank