2002 blazer, 4.3 vortec rough idle

So far I only replaced (tps) still runs rough I am not getting any code from engine computer, it is running rich you can smell it and still does not set off check engine light??? don't know why? It seems to runs o.k.once moving! I had a friend hook his diagnostic computer to it all sensors check out as o.k he's also baffled?! do you think i have a bad ground somewhere????

this may seem to be a repeat but i read alot of the other post's on 2002 blazer rougn idle mine is unique though esveryone else seems to be getting a check engine light and a code. I get nothing??? but rough idling.

What is wrong with engine computer my 1996 cavalier goes off at the slightest glitch.lol

$480.00 later replaced catalytic converter, distributor cap???