2002 2.5L V6

immediate codes P0037 P0057 P1646 P1647.

Would there be a common link for all four 02 sensors to consistently log a fault?

All sensors couldn't all be bad ?!

Maybe a common ground?

About to run through the pinpoint tests so I guess if I solve one then it will solve all (if a single common issue affecting all).

 

Look at EMS control relay, F38 and F42 in the POWER DISTRIBUTION FUSE BOX (figure 1.6 and 3.1 in the Electrical Guide S2002_XTYPE.pdf)

 

F38 and F42 (30A) both continuity.

R7 (EMS Control Relay)...if that was faulty wouldn't that cause far greater grief than just O2 sensors?

 

So the mystery continues. I followed through the troubleshoot procedure for the easiest accessible and result was prob sensor bad. ie. ran through the entire test process and arrived at the final..."it must be a bad sensor" default result.


Was hoping to solve one and solve them all.

So will replace one sensor and consider possibly all are bad (maybe need an ultrasonic bath?).

Meanwhile continues to run open loop and fuel economy is still around 10 L /1ookm which is around spec/quoted anyway.