hi guys, i got a 98 4.0 with about 85k. engine was shuddering and not very responsive followed by the check engine light. plugged in my obd II and got no codes at all. my first thought was a bad O2 sensor, but wouldn't that show up on the OBD II system? Do I need a Land Rover computer to get a reading or is there an on-board computer in the dash?

thanks for your help. adam.

 

Yea you need to use Testbook

 

what is test book please?

thanks again. adam.

 

All NAS vehicles are required by law to use the same codes for any problem that will illuminate the CEL. A O2 sensor will NEVER cause a noticeable drive-ability issue.
If the CEL is on there should be codes stored that are readable by anyone with the proper equipment.

 

If its not a emisions problem your gonna need test book to read it. Test book it a LR CS that will dig the problem.