I have a 2003 Toyota with a check engine light on. The car runs fine but my Texas emissions test is due by the end of month and they won’t test with a check engine light on. Any help with this is greatly appreciated.
I got a readout by autozone that reads as follows:
BB Catalyst efficiency low-bank1
Probable cause :
bb1 catalytic converter defective(failure possibly due to #2, 3, or 4)
bb2 engine misfire or running condition
bb3 large vacuum leak
bb4 engine oil leakage into exhaust-valve guide seals piston rings
bb main catalyst efficiency below threshold bank 1
explanation
bb faulty catalytic converter
probable cause
bb1 rich air/fuel ratio
bb2 air leak near rear HO2S
bb3 faulty fuel control HO2S
It sounds like the most probable cause is an intake air leak after the MAF sensor or a exhaust air leak before the O2 sensor. Check the vacuum hoses and make sure there isn’t one that is disconnected. Check for a intake manifold leak. It may also help to look at all the plugs and see how they compare with each other. If one cylinder is running too rich it may lead you to the trouble.
You need to post the actual code, not their computers interpretation. The P0420 is a common code for this vehicle and it can be a bear to get fixed. If you have it, I would try cleaning the connectors to the computer and teh front O2 sensor before buying any parts.