LT5 wont run with all cylinders

[Mika73]

Originally Posted by 95ZR1

What did you do, put leaded gas in that car? I wonder why they kept saying 2 and 7 weren't firing right if the cats were bad.

First question: NO. They dont even sell leaded gas anymore here at Finland. And I didnt use diesel fuel either.. And then back to business.

I dont know why 2 and 7 didnt firing right and O2 reading was max.

But everything looks normal after cats were removed.. Engine did run ok with headers only and O2 sensor reading was normal.

I dont know why. They think that I got bad chip that did kill my cats.

I dont know why this all is happening..

Those RT cats did last two days and 120miles.. Its quite expensive..