Arrhh! Another problem! Engine check light on!

[BLUETHUNDER]

After the problems ive had with the windshield washers,and my crappy iginition switch,i thought nothing else could go wrong but it has.

I went and put some gas in it yesterday morning and after 30 mins the engine check light came on. Its on constant. Not flashing. Thought i may not have put the gas cap on properly. But it was. Then suspected that maybe ive used some ****ty gas. I then went and put some premium stuff in. But still no joy.

I went to see a mate this morning who is also a mechanic. For some time now i have suspected that the cats are on there way out. My friend comfirmed this by tapping the cat gently with a rubber mallet. He said its all broken up inside and thats why i'm getting the light on.

I said ive had cats go before on vehicles and never had a light come on. But he said on the Hummer you have two 02 sensors per cat. Its the sensors that are after the cat thats getting a incorrect reading due to the cat being broken up inside. Could this be true....??.

Looks like i will be ordering some universal cats from Rock Autos. Anyone else used them??.