O2 Sensor Heater Codes with Meth Injection

[BigBadBen]

I recently installed an HFS-6 system on my Porsche 996TT. I am running a 75/25 meth to water ratio.

I have been getting an odd code coming up only when I am running my Aquamist system whereby the front 02 sensor heaters seem to be throwing these codes.

I am running a catless 3" exhaust.

P0155 Oxygen Sensor Heater ahead of cat bank 2
P0135 Oxygen Sensor Heater ahead of cat bank 1

When I switch back to my pump file with no meth injection the codes do not come back so obviously the sensors are fine!

I am wondering if the meth injection is fooling the DME into thinking there is a problem with the 02 sensors because of the unexpected low temperature readings at the sensors when the meth is being sprayed.

Any thoughts please.

Cheers,

Ben