Quadcammer

Hey gang,
I'm running into some Check engine issues with the downstream 02 sensors. The heaters on both seem to be kaput resulting in p1117 and p1121 codes.

Although the sensors haven't been replaced for a while, I would find it odd that they both **** the bed at the same time.

I'm a bit concerned that this is the result of a bad engine harness, even though thats been replaced under the recall/tsb.

What I've done is undo the connectors, clean them with electronics cleaner, cleaned the engine bay grounds, reset the DME relay and plug to the ECU.

Can anyone give me diagnostic advice on how to determine if its the 02 sensors or the wiring harness.

I'm assuming I can check the resistance of ECU port 20 to the wiring harness plug in the engine bay to check if there is a break in the wire?

Also, checking the heater by ohm'ing the circuit?

Any advice would be helpful.

I should note about 4 years ago I got the same code but it went away by doing the cleaning of the ground and resetting connectors.

Thanks very much chaps.

Quadcammer

ok left side heater is 840 ohms of resistance. right side is 4.5 ohms.

off to amazon

rlme36

When I swapped out the ones that are easy to get to when I put in the Fisters rockauto had good pricing on the Bosch units.

Quadcammer

yup, they are good, but with shipping, amazon is cheaper.

bout 75 bucks each, no biggie.

Quadcammer

just to close the loop, replaced the bank 2 downstream 02 sensor and all is right with the world.

993Godspeed

Glad to hear.