Ok so i ran the codes from my truck and came up with this....

136: (R) Oxygen sensor not switching/system rich Left or Front HO2S - Fuel control

173: (R,M) Oxygen sensor not switching - system is or was rich - Single, Right or Rear HO2S - Fuel control

411: (R) Idle speed system not controlling idle properly (generally idle too high) - ISC

412: (R) Idle speed system not controlling idle properly (generally idle too low) - ISC

538: (R) System did not receive "goose" test - TESTS


I got an odd one too... Its 437 and i can't find a explanation of this...


So here is my question... what could be causing these codes? Could it be O2 sensors? or is there another problem... Any help would be awesome thanks

What engine you got?

We've got a nice section just for EEC Diagnostics. I'll move this there for you. :)

Thanks for the move, its been a long day. Its finals week, WOOHOO.

Its a 4.0. I just can't seem to find the extra code and what it means

I have tried everything and can't figure out what the problem is?