Engine Check Light

[r34liner]

hi all

my lexus is300 (scarfaces old ride) threw a engine check light,

code p0141 o2 pre heater circuit, bank 1 sensor 2, im guessing that its the sensor near cat?

i was told it had a 02 simulator already installed before full decat 2 weeks ago, didnt throw check engine light until i had done 1200 miles,

any replys or how to fix this would be greatly appreciated as its costing me a fortune in petrol!!! lol

louis

[stuie]

hi all

my lexus is300 (scarfaces old ride) threw a engine check light,

code p0141 o2 pre heater circuit, bank 1 sensor 2, im guessing that its the sensor near cat?

i was told it had a 02 simulator already installed before full decat 2 weeks ago, didnt throw check engine light until i had done 1200 miles,

any replys or how to fix this would be greatly appreciated as its costing me a fortune in petrol!!! lol

louis

Have you tried just doing an ecu reset?

[Adie]

Have you just had the main cat removed??

[r34liner]

ive done a ecu reset and had the codes cleared with diagnostic tools, did 6 miles and light was back on with the same error code,

thanks for your reply

[Adie]

Have you just had the main cat removed??

[r34liner]

just done full decat including race headers, decat pipe and hks hipower rear section,

scarface said it had a 02 simulator installed by mark of tdi

[Adie]

In that case then mate, I am afraid you will get the CEL light come on from time to time. I've got a full decat system on my IS as has DazaW and we both still suffer from it. We've also got O2 sensors fitted but unfortunately they are still not a permanent solution. Something to do with Lexus using different sensors.

Nobody to date has been able to find a permanent solution for this problem. Its still a case of just resetting the ECU when it comes on which is a pain in the arse but for now we have to put up with it.

[r34liner]

i can reset my ecu, but not every 6 miles, hardest car ive ever had to decat, its dog slow with cat put back in, my check engine light is perminantly on and wont go off

[Adie]

I find that my CEL comes on more the hotter the weather is or after long motorway journeys..

Does it come straight back on after you reset? Maybe you've damaged a sensor? Or not refitted correctly?

But as I say unfortunatley it will come on if there's no cats fitted.

[r34liner]

i would just remove bulb from dash, but as soon as light came on car runs like a bag of ****, missfiring and stinking of fuel as ecu must go into some sort of safe mode and throw far to much fuel in, tell truth ****** off with car at minute,

[Adie]

Can't just be the Decat pipe then. You say you've also done more performance mods to it.. Have you had the fueling checked? Have you checked the spark plugs, coil packs etc?

[r34liner]

yeah could leave it ticking over on my drive and cel would be on, maybe get sensors tested to make sure

yeah just changed plugs, the ignition seems fine just overfuelling causing the car to miss and stumble on low throttle, is sensor 2 bank 1 the cat sensor

[ColinBarber]

We've also got O2 sensors fitted but unfortunately they are still not a permanent solution. Something to do with Lexus using different sensors.

They are pretty standard sensors on that engine.

[ColinBarber]

yeah could leave it ticking over on my drive and cel would be on, maybe get sensors tested to make sure

yeah just changed plugs, the ignition seems fine just overfuelling causing the car to miss and stumble on low throttle, is sensor 2 bank 1 the cat sensor

bank 1 sensor 2 is one of the sensors on the manifold before the cats.

The error produced is a problem with the heater rather than the O2 sensor itself. It checks this by measuring the current going through the circuit. If you are using an O2 simulator then it needs to be a 4 wire one with the heater circuit having the same resistance and the original sensor.

You can always use a simulator just for the O2 circuit (two wires) and connect the other two wires to the original sensor.

[MrADeveci]

Hello mate .......... Im sure the 02 simulator is only good for the pre-cats ............ and not for when you take out the main cat.

Didn't TDi also make a solution for the main cat, as like on Daza's car ... he had the same prolem when he took out the main cat!

[r34liner]

many thanks for all the replys

i will give mark of tdi a ring and try to get this sorted, many thanks

louis