No CEL with key on

Starting to think something is wrong with my check engine light because it does not show up before the engine is started. Anyone have any input or experience working with the cel? I assume its an led but cannot find any information on it. Getting it scanned tomorrow to see if its putting out any codes.

 

Damn P0430, P0420. Somebody wanted to hide something

 

Bought a used car and the CEL was disabled??

Could just be a bad O2 sensor.

EDIT: depending on the odo stamp for the fault haha if its been there for thousands of miles, making your a/f ratio fubared....monolith probably looks like ramen noodles.

 

Apparently so. I never put it together til a few weeks after i bought it and did not see the cel showing when key on. Im gonna ohm out the sensors and see if that turns anything up and if not ill have to look into cats. Truck has 123k

 

Really need to get it on a tuning software or something to see if theyre switching properly but dont have hp tuners.

 

I would check them yes and also check wiring ie continuity, voltage supply.

Even if you found a bad sensor though you will need to check the condition of the Cat. You would be surprised what a couple thousand miles of poor A/F will do to it.

 

Update:
Got the light on and heres why it was off. At least they didnt attempt to screw with the circuit board. Jackasses.

 

That duct tape?

 

Electrical tape

 

And it was behind the overlay

 

I hope you bought it from a dealer.

 

A dealer yes, a big dealer no. It was a good deal and I cant believe I missed not seeing the light the three times i went to examine the truck before buying.

 

Aww man that's not cool. What a bunch of assholes! Did you buy it at a car lot?

 

Whoops, updated while typing haha

 

Got that right.

 

Hopefully its just o2 sensors. If not im gonna try the acid bath for the cats

 

Update: Got my diagnostic software in and been monitoring things. o2's seem to be working good and catalyst temperatures seem normal. Cleared the codes and it took 100 miles to activate the cel but the codes were pending within 30 miles. Gonna try the o2 spacer trick to verify its the catalyst and go from there.

 

Don't know what state your in, but in California anydealer (regardless of size) that disabled a check engine light would be in deep, deep trouble!

 

Yeah, we dont have emissions testing or inspections in Oklahoma

 

Doesn't matter. Emissions are covered under Federal law.
That is a bigtime EPA violation.