Check engine light came on

[hoodsdakotas]

So I tryed to get the code with the turn key on/off trick. But it said CHEC. Not sure what thats suppossed to mean. Thats what I was doing is checking it. anyone have any ideas.

[YAAAABUDDY03]

Sell it!























































lmao... just kidding... Take it to a dealer or a shop or somewhere that has a computer where they can hook into your trucks computer and figure out whats going on.

Paul

[mopar rt]

Try it a few more times. Key on and off three times then you should see some codes. Do not delay between on/off if you wait too long it will not always work.

[supradakotaman]

I got that about two weeks ago...I went in to autozone and borrowed a code reader for free. My problem was my gas cap wasn't on properly...damn cheap pos locking gas cap replacement. But head on down to autozone, they rent the code reader for free.

[rockadaous]

So I tryed to get the code with the turn key on/off trick. But it said CHEC. Not sure what thats suppossed to mean. Thats what I was doing is checking it. anyone have any ideas.
shot in the dark
check your gas cap and make sure it's on tight. Did you replace it lately?

[hoodsdakotas]

thanks for the help. Ill check out autozone.

[rockadaous]

http://www.actron.com/publish/2004/10/22/pdf_english_16298.pdf

here's a good list of codes when you find out what it is....

[hoodsdakotas]

Got it. It is PO420. Catalyst efficiency below threshold(bank 1).
Im not sure what that means. Im guessing its either the cat or downstream O2.

[rockadaous]

what I normally do is google the code I get and this is what I came up with

Q: Can you tell me what OBD Code P0420 “Catalyst system efficiency below threshold (bank 1)” refers to? Is this an O2 sensor problem or does the catalytic converter need to be replaced?

A: The computer in your vehicle uses an oxygen sensor in front of and behind each converter. The converter processes and reduces exhaust emissions. The computer program knows that there will be a difference in the information being reported from the front O2 sensor and the rear O2 sensor as the converter processes the exhaust emissions. As a converter ages it becomes less efficient. This loss of efficiency is known by the computer because of the information that the O2 sensors mounted before and after the converter report. Just because you have a converter efficiency code doesn’t always mean the converter needs to be replaced. A defective O2 sensor can cause this code to be set by the computer as well. Your technician has to check the O2 sensors to be sure that they are operating correctly and that other related systems are doing their job. If all checks good then a replacement converter is needed.

[hoodsdakotas]

Thanks for the info. I found the problem. The cat was clogged. Eventually I lost probably im guessing around 100 hp!!! Very very slow. So I fixed it. And it has more power than it ever had. Plus im getting better gas mileage.