my explorer failed emissions test
 

They checked the gas cap, it was ok... they went to check the check engine light... it does NOT come on with key on engine off.... they failed it at that point.... I am new to the obd II system and the related systems... any help will be greatly appreciated... my thoughts are blown bulb in cluster, a blown fuse .... by the way it is a 1997 sport with a 4.0 sohc engine with 135000 miles on it.. :-huh :mad:

that one is an exploratory surgery kind of thing. Blown bulb--bought used, bulb removed---power up problem on the pcm---ground problem on pcm

Yep.

Replace the bulb--fail bulb check you fail inspection automatically; get codes scanned--why bulb was removed in first place then come back to us with said code numbers so we can help you.

replaced cel bulb....
 

and two others behind dash.... no problems....other than my shift indicator is not right... it came out a bit when I moved cluster to remove the #74 and 2 #194's behind...but now the cel comes on as it should when you turn the key on,engine off... illinois' emmissions failed me because of this....would not even continue the test to tell me if there were other problems,lol...beaureaucratic bs...at it's best...have driven it about 2 miles since I replaced bulb...no cel on....so ,I guess until I get a obd II tester ...its all good!...thanks for all the input....if it fails again,i will have the autozone or murray's folks pull codes for me....mike

pulled the cel..codes...
 

now i need some help....the codes I got were:

PO442 evap emissions leak (small).....this one I knew... you can hear it...

PO430 cat effiency below peak(bank2).....

I erased the codes and have not seen the light come back on....although it was only a 3 mile ride from the Murrays by my house ...home.....

any input will be helpful......

I will be buying an obdII tester soon... I looked at the one from harbor freight for 39.99 on sale -any good....or should I spend the extra cash and get the better ones to erase codes as well? again any input will be helpful.....thanks ...mike