Hi All,

I picked up a 2000 XJ8 for $800- owner said broekne timing chains, but I found it to be Bore Wash. (don't worry, I replaced the tensioners anyway) Here's the deal-

Car starts and runs fine. My reader shows it running in open loop, no readings from the o2 sensors or any mixture readings. Car is up to temp, I tried two different readers FYI.

Not sure where to start, as I need to get it through the paces so I can get it smogged.

 

Is it setting codes?

If there are not codes perhaps you are not linked to the ECM data that provides the fuel trim information. Can you see any of the expected data other than fuel trim? Temp, rpm, etc.

 

I get temp, TPS, and a couple others... I am wondering if maybe the reader is SHOWING OL, but it is actually running closed... Going to check the connector and bulkhead connection tomorrow as well as the brake switch to see if there is an issue there. It is running fine, but I need to get it to smog without any codes. I'll post the codes when I pull them tomorrow.

 

You can also look to see which OBD monitors have set and which not. Those can be a hint to what may be wrong.

If there are no actual codes, next look for pending ones.

 

Ok- P1647 appears about 20 seconds after resetting the codes.

 

Swapped o2 sensor connectors and now it's P1646... On the hunt now.

 

Swapped them and getting P1647 again, so it looks like I found the winner. Still wont go into closed loop... Here are my readings:




Open loop! Temp is up after a freeway drive.





O2 readings jumping around, so shouldn't they still be good?





Anybody kno what EQ ratio is and why it's stuck at 999?<br/>

 

RESOLVED-

I switched the driver's o2 sensor with one from another car and BAM- everything lights up normal and I am getting readings from all sensors.

 

Wow !

Awesome deal

 

Thanks!

 

On a side note- I was able to trigger all the emissions test cycles by starting the car, idling for 7 minutes, then driving regularly for 3 minutes, then driving 10 minutes at 55MPH and finally driving 35 MPH for 30 seconds- hope this helps someone!