How Many of you ......

[SilverSchoolBus]

Have had TMS stage 2 done and EML came on with 042011 error code?

Also, how many of you have tried to fix it with no success or just decided to drive with the EML on?

Cheers, Silver.

PS NO tuner war PLEASE!

[tin545]

ive had this fault code before,but it only flashed for a second then went back to 0000000 an now it dosnt show at all.i never changed or done anything so its a small fault that exists with performance exhausts.i think its to do with emissions

[Ojc]

I had a couple flash up the other day, car went into limp mode. I pulled over, turned it off. Left it a few seconds, flashed the codes up with the pedal thing. Turned it back on, no EML light and no issues with performance.

Weird.

[Phatashki]

To be honest, Most if not all performance exhausts have the same problem, even more so if the car is mapped, Mine has come up a couple of times and once i check what it is I just clear it.

I think the zaf's and astra's must have a very small tolorence for emission values and so as soon as the sport cat is fitted it notices somthing isnt right and throws up the code.

It will pass an MOT fine mate.

[SilverSchoolBus]

I had a couple flash up the other day, car went into limp mode. I pulled over, turned it off. Left it a few seconds, flashed the codes up with the pedal thing. Turned it back on, no EML light and no issues with performance.

Weird.

That is my fear, lol. As long as I am not damaging things and it doesn't put itself into "limp mode", I suppose I can live with the little light on the dash, lol. However, it would be nice to find the problem and fix it!

[BLADRUNNER]

had this on mine took map of and put stage 2 back on ok now had this 2 times know

[andriano]

There is one way to fix this but you will then never now if the cat fails

To block the o2 sensor or put a de-cat map on then the light and code wont come up

[VX220T]

P0420 Cat System Efficiency Below Threshold can occur on cars running a high flow sports cat, usually 100 cpi, but sometimes 200 cpi. More usually this occurs on cars running OE software than on remapped cars, (depending on which software is being used on a mapped car).

On a standard mapped car, because a sports cat is higher flowing, and so filters out fewer of the 'nasties' the second lambda sees higher emissions readings than it is expecting to see, because it is using lookup tables written for a map written for use with a much denser catalyst i.e. an OE cat which will produce fewer emissions. So the EML comes on for P0420

On a remapped car if the P0420 DTC is written out of the map or the thresholds are correctly altered then the EML will not come on for this P0420 fault code.

Simples! (All the above assumes that an O2 sensor has not been damaged during exhaust fitment)

[SilverSchoolBus]

There is one way to fix this but you will then never now if the cat fails

To block the o2 sensor or put a de-cat map on then the light and code wont come up

Thanks for the solution but hmmmmmm, i am not too sure about that, lol.

[andriano]

Thanks for the solution but hmmmmmm, i am not too sure about that, lol.

Good to be a help.

I dont see what you could loose by blocking the O2 sensor but i would go careful and speek to the tuners about the de-cat map though before putting it on, if you are thinking about that

[VX220T]

speek to the tuners about the de-cat map

Exactly as I said! If the map has been done correctly, whether the exhaust does or does not have a cat, that error will not bring the EML on. If TMS can't do it I know Courtenay or EDS can.

[SilverSchoolBus]

Exactly as I said! If the map has been done correctly, whether the exhaust does or does not have a cat, that error will not bring the EML on. If TMS can't do it I know Courtenay or EDS can.

Exactly, too, lol, all they (the programmers) have to do is just increase the tolerance further, if it was +/-5, how about +/-10, that should stop the code and eml coming up and I can't see what sort damage it can do to the car apart from it is not too obvious to spot a failed cat, well, the mot tester would let me know that I suppose, lol.

[moosh]

Ive the same map and not had it mate.

Ive got the remus exhaust if that helps and it was on it a year before i put the map on it.

I have had bother with the O2 before but it went away. Only happend when the car had been sitting idling for ages then i took off and the light came on but that was before i mapped it. Its been fine touch wood since i mapped it. I did have bother with a boost solinoid and air flow meter but replace them and car is perfect.

[paulk]

was a big problem on my car...stage 1 2 and 3 but tms/superchips sorted it