robin427

P0135 - O2 heater bank 1, sensor 1
P0155 - O2 heater bank 2, sensor 1

I have replaced the rear O2 sensors with simulators - is this why this code is coming up? The rear O2 trace comes up with a square wave, which is generated by the Baker module. The front O2 trace is steady at about .48 at idle

P0412
P0418

Both AIR codes - I've removed this system

P0443/P0449/P0452 - EVAP codes. Again, I've removed this system too

P0704 - Clutch switch... don't have one as not using original pedal box
P0803 - Skip shift - it's unplugged

So, nothing to worry about, I think but will these codes reoccur since I've cleared them?

Black02SS

iTrader: (36)

The only ones I see to worry about are the O2 codes. They are for your front oxygen sensors and not the rear's. If you are seeing the a flatline on your front O2's and are still using closed loop, then I would replace the front's.

robin427

Define "closed loop"? Could it be because the O2 heaters weren't powered? I'll check the fuses...

txhorns281

iTrader: (12)

Could be that, could be O2s just going out, could be a break in the circuit somewhere, watch out for it again, if it comes frequently, like black02 said, your O2s suck.

Closed loop = search

MrDude_1

iTrader: (4)

check the fuse for the O2 sensors.

btw Bank 1 means drivers side. Bank2 means passenger side.
Sensor 1 means front O2
Sensor 2 rear O2

since you removed the AIR system, disable the AIR codes in the tune.



same as above.. disable the codes... btw, what are you currently running for a gas tank vent?



disable in the tune, or it'll come back.

either plug it in and set the tune for it not to come on.
or
disable the code in the tune
or
stick a resistor in there.

i prefer #1 since it kills the skipshift light too. (atleast in stock cars...)

they'll all come back if you dont fix why they came on.
the front O2s will considerably effect how the engine runs. the rest of the codes you can ignore.

robin427

Re: fuel tank vent - I've transplanted the engine into a Cobra - www.creffieldcobra.co.uk, I've got no MIL set up at the moment, and as soon as I've got HPTuners, I'll delete the codes permanently...

What difference to the running of the engine do dodgy O2s make?

MrDude_1

iTrader: (4)

well, to me it sounds like the heater circuit doesnt have power.. its unlikely both O2 sensor heaters failed at the same time..

in anycase, when the O2s fail, the fueling goes really rich..(ive heard around 25%) this causes the engine to run a little rougher at idle, and your MPG goes to ****. long term driving like this accelerates engine wear, since the cyls get the oil washed off of them by the fuel.

robin427

Thanks, when I rewired the loom, I put them on a separate 20A fuse - will check to see if it has blown... what value would you recommend?