2005 Cadillac DeVille Check Engine Light on Due to Faulty Catalytic Conveter

Failure of the catalytic converter can result in illumination of the Check Engine Light .

Affected Model Years

This issue affects Cadillac DeVille model years 1991, 2000, 2001, 2002, 2003, 2004, 2005, .

56 people reported this problem

  • 2005 119,787 Miles
    Cat failure. Replaced Cat and less than 2 months later the Cat failed again

  • 2005 130,000 Miles
    Check Engine Light on due to catalytic converter

  • 2005 160,000 Miles
    code. used treatment with "seafoam" engine spray and lube $ 10 vs $ 300 after market converter or 1000 oem

  • 2005 150,000 Miles
    Codes p0420 and p0300 are coming up. Replacing catalytic converter. There is only one right? The p0300 came up 2x on dash.

  • 2005 0 Miles
    Right after I bought the car the check engine light came on so I am not sure when it actually started. I bought it second hand. i have not fixed it.

  • 2005 72,000 Miles
    replaced catalytic converter a few days latter light came on again. replaced sensor, light came on again. mechanic said needs to be programed.

  • 2005 166,500 Miles
    Check engine light came on and coded that it was an issue with the Catalytic Converter. Totally sucks.

  • 2005 144,000 Miles
    need new catalytic converter

  • 2005 0 Miles
    Engine keeps getting hot also check engine light is on. Changed. Water pump radiator hoses cap gasket sealant flush. Don't know what else to do

  • 2005 220,000 Miles
    Insalled Walker catalytic converter, $ 128.00 on Ebay. 6 weeks ago...still good

  • 2005 81,000 Miles
    Catalytic converter wore out, replaced

  • 2005 81,000 Miles
    Ruff idle shinning sound vibration miss fire changed coil pack and spark plugs same problem persists

  • 2005 160,000 Miles
    pipe burn red at the back of catalytic pipe

  • 2005 175,000 Miles
    I had light on CHECK ENGIN went to local Cadillac Dealer and was informed it was the CAT.Con. and I required a new one @ 3667.00 plus labour so I went to a well known muffler shop here in Kelowna,B.C. Canada and had a generic one installed for 350.00 inc. tax.labour and productand it runs just fine now / I was an un:suspecting buyer it had been a taxi in Culver city Ca. sold to a cab. in Nevada / and mills were rolled back to 50.000 miles/ I got all this info after I bought it from car fax ?? / I paid 7200.00 and spent about 3000.00 but it runs like a charm now / but get a used car checked befor you buy I never would have bought a used taxi/limo. [email protected]

  • 2005 70,000 Miles
    Just out of the 6 year / 100K certified warranty. It cost me over $ 1000.00 to repair. I was told this is because engine oil consumptiom burns them out.

  • 2005 46,667 Miles
    This car needs a Catalitic converter.....This will be the third Cat. on this car since we had it ....car sits all summer.....came back to Florida.... light came on ......went to parts store....they said it needs a catilitic converter. We put on 20,000 miles since we had it. Now it needs another cat.......WOW!