Engine Management Light P0300

[colwill197]

Hi All,

So the EML has come on twice in the last 2 weeks. First time I lost all power and had a message telling me to stop. When I let go of the accelerator it would rev to about 2.5k then if I put pressure on it, it would drop. Restarted the car and no trouble. Then last night it randomly started flashing with no error messages whatsoever. After about 10 flashes it stopped.

I got the OBDII reader out and it gave me P0300x2 one logged and one pending. The logged one I imagine the one two weeks ago and the pending one, the one that happened 10 minutes before and the car had not been restarted since.

So obviously after doing some research there are a few things it could be. Lambda sensor, spark plug, crank sensor, coil pack etc. My car has done 48,000 miles. I changed the sparks around 6 months ago so I dont think its that.

I am hoping its the lambda sensor as I have changed the exhaust around multiple times in the last few months so could that have damaged the secondary lambda sensor from movement and knocks etc. If so what am I looking for with the OBDII reader?

Are there any ways through live data to tell what the problem could be. Rather than me go on a wild goose chase. Also anyone know how much a lambda sensor is?

 

[colwill197]

Bump please cheers

 

[jakehewitt]

[MENTION=33565]colwill197[/MENTION] Do you have an enlarged throttle body?

 

[colwill197]

No I don't. I'm hoping it's the second lambda sensor. I have an OBDII live data reader. Is there a way of spotting a faulty lambda through one of the readings.

 

[jakehewitt]

If you have the torque app you can use the live data for the lambdas and determine it that way

 

[colwill197]

What am I looking for which readings will be out?

 

[Foxspeed]

looking at voltage swings on the readings - when they go faulty the switching of the voltage goes slow...

second lambda is there to check one the first one to make sure its working within range - its usually the first one that upsets the engine running

 

[colwill197]

Okay will do. I am quite sure it's the sensor as coil pack surely wouldn't recover and spark plugs are recently changed..

 

[Foxspeed]

that code is the multi-cylinder misfire iirc - you will be lucky to actually find out what is causing it - there are if you check been plenty of reports of that
on here - even mine did it a few times - I never found the fault but it never did it that regularly

 

[jakehewitt]

It took me 3 months to sort out the same problem on mine, had the same symptoms. Turned out it was the throttle body, switched that over back to standard and not had the problem since

 

[richwell]

I've recently had problems with a coil pack - the error code did tell me which one was playing up.

Do your code reader allow you to see the voltages of the lambda sensor?

 

[colwill197]

Hi mate,

Yeah it does and it seems to be switching between 0.1-0.7 so I think thats normal. It seems to be re-reading and switching regularly too but my OBDII reader is quite slow so cant tell if its faulty I dont think.