My 2003 4wd blazer was just bought not so a month ago, the radiator is little dirty and the blazer was parked before I bought it.. Will get it cleaned soon but when I go at 50 mph in 3rd gear, I feel as it starts to hesitate then mph will decrease and rpm will force itself to increase.. If I keep doing this, the temperature will increase... And the gas goes bye.


However when I bought it, it ran smoothly and beautiful..

Cleaned mass air flow sensor today, no changes..

Codes shows
P0101
P0303 ( those two seems related as it could be a cracked line between those two by my mechanic but not determined yet)

Then more codes:
P0300
P0420. Catalyst threshold bank 1 confirmed

I think it may be catalyst system..

So I'm thinking of pouring catalyst cleaner tomorrow and see how it goes..
No big informations yet.. Finding it as I go.. But any other ideas really?

 

Did you figure this out? My 2002 threw the P0101 and P0303 codes yesterday while pulling up a long hill on highway at around 70mph. Engine bogged down when it happened... Did it twice on a 220 mile drive, then was fine on the return trip.

Thanks for any info.