Jump to content

2018 Silverado

frustrated andy
 Share

Recommended Posts

frustrated andy Enthusiast

frustrated andy

Posted
Posted

I have a 2018 Silverado 5.3 the check engine light stays on ,code 420 and 430 . I have replaced the exhaust (y pipe back) and the sensors , I've replaced the spark plugs and wires light is still on and reading the same codes. Need help with it 

rav3 Senior Enthusiast

rav3

Posted
Posted

Did you ever clear the codes?

CamGTP Senior Enthusiast

CamGTP

Posted
Posted

Those are cat codes, did you actually replace the cats themselves?

 

You typed you replace the y-pipe back, does that mean the y-pipe itself or the cat back?

 

And did you go with OEM or aftermarket?

 

If aftermarket they usually set a check engine light. You can try to space the rear sensors out of the exhaust stream some to not trip the code.

rlcole321 Enthusiast

rlcole321

Posted
Posted

Now did you replace the exhaust parts "Because" of the codes, or for another reason?, your mechanic should be able to read the DataStream to see if the O2's are within their respective ranges, like upstream O2's should fluctuate between .100 to .900 vdc rapidly, and the downstream O2's should stay high about .700 to .900 vdc all the time (with veh at temp.) Did you replace any O2's?  You can buy a fairly good OBDII scanner to read this data at fairly low prices.

frustrated andy Enthusiast

frustrated andy

Posted
  • Author
Posted

The truck has went into a safety mode because of the catalytic converters codes. I've called a Chevrolet garage to come get the junk 😡. 

 

CamGTP Senior Enthusiast

CamGTP

Posted
Posted

Cat codes themselves should never cause reduced engine power, I've never seen that before.  A different issue surely could though.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • jgaudet99
      Tire psi

      By jgaudet99 · Posted

      Thank you, I'll check that Autel scanner out and see if it will work for me! Ya I can see GM's point of view if they lower the psi set value for someone and the person sell's the truck and the new owner puts the factory tires back on then their could be liability issues cause the psi warning light wasn't coming on when the tires were under inflated for towing their load and then it might be able to be traced back to GM lowering it.
    • Chuck FB
      Tire psi

      By Chuck FB · Posted

      I had a similar but different response when I talked to the service manager where I bought my truck in that he said GM corporate won't allow them to lower the placard pressure setting as they would get their hand slapped but that of course they have the ability to make that change. His suggestion was simply go to a tire dealer or third party shop that is willing to reset the pressures lower. However I chose to buy a tpms tool and partly based off of this very forum as it had been proven to work on the 2024 model ( Global B system ) and while I could have paid lots for a full two way diag tool, I didn't want to spend that much and bought the recommended Autel TS 508 and it will reprogram the 2025 model and assume it should do the 2026 as well. However the tool is rather proprietary to reprogramming Autel tpms sensors so that is a function I will never use, where as a real two way scanner would have many uses but also have yearly subscriptions etc where this 508 is free updates for as long as they put updates out for the unit. In any event it worked to lower the placard pressures and I often use it to adjust my actual tire pressures although will check with a mechanical gauge as well sometimes just to make sure that tires tpms sensor isn't lying to me.    My suggestion is either buy a tool that you know will work to adjust the system or start out by getting the tire shop you bought your tires from to reset your truck and if after that you still want a unit to do it yourself, get one at that point. 
    • jgaudet99
      Tire psi

      By jgaudet99 · Posted

      Here is an image of a quick Google search about these tires on my truck and it's exactly same psi recommendation the Toyo tires company gave me!    I'm not looking for anyone else recommended psi or anything, I'm just looking to see if anyone knew a way to get rid of the factory low psi warning light, because I'm not running high psi and ruining my tires when I'm not towing! 
    • jgaudet99
      Tire psi

      By jgaudet99 · Posted

      60psi front and 80psi rear But I am not running the factory tire brand or size! it's load range F Toyo tires
    • newdude
      Tire psi

      By newdude · Posted

      Open the driver's door jamb.  What do the cold tire PSI ratings on the tire placard show?   I'm not saying to run it to those numbers, but I would like to know what it says.      

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...