I have a 2006 5.3 z-71 Silverado x cab with 143,250 miles. I haven't driven it much for the past 4 months maybe 300 miles in that period, this past monday I drove it for about 60 miles and everything was good, it was parked til Saturday and when I started it started to drive I noticed my check engine light was on, it stays on in idle and blinks when I am driving. I live in central California and the weather has been pleasant, any suggestions. My gas cap has not been removed for the past2 weeks but it seems to seal good.

 

Take it to an auto parts store and they have a device they can hook up to the truck and it will diagnose it and tell you where the signal is coming from. We used it alot so my father ended up buying one for us to use. but go to an auto store like pep boys or auto zone and tell them about it and they can hook up their machine

 

Thank you Chevy-guy 3. I did take it to a mechanic and the scanner said mild misfire. So I changed the plugs with oem ac/delco's and disconnected my battery to reset it the light but it's still on. I am replacing the wires tomorrow see what happens. It was due for a tune -up anyway. by the way the guy at the autozone here in central California said that California hasn't done scan diagnosis for over 7 years , he said it was a law.

 

get the misfire fixed pronto. misfire conditions destroy catalytic convertors.

 

No problem glad i could help! sometimes you just have to drive it for a while to get enough miles on it for the indicator to go out. but if you are positive that it is fine and it wont go off you can also get the indicator reset at the store

 

Thanks, I will put the new Belden wires today and see what Happens.

 

Tech 2 do you have any suggestions for me? I just installed new oem plugs new (Belden ) wires I disconnected the battery for a couple of hours and on restart the CEL went off but it came back on after a minute or so. What can I do next, I still feel a very slight miss when the tranny shifts to second gear, nothing harsh I just feel it's missing. What can I do next on my own, before I take it to a mechanic?

 

you need to isolate the misfire to a particular cylinder. to do that, you need a scan tool that can access misfire counters.

 

I will take it to a mechanic. Where can one purchase a good inexpensive scan tool? I know they can get expensive.

 

Took it to mechanic said it was the number 8 cylinder, so I will return it to him tomorrow to start working on it. What are the reasons it's misfiring, coil or what else can it be ? I sure hope it's not a valve or something drastic like that, I will see tomorrow.