Basically I think this might have started when I attempted to clean the EGR passages in the in the top of the Intake manifold. . The car hasn't thrown any codes until today when I put some BG44K in my tank and fueled up. The motor sounds like it is trying really hard to move the car, intake is more prominent sounding like the ebrake is on, which of course it is not. I had my mechanic swap in a AV6 and the problem persisted. I picked up the car today and it finally threw a CEL. p0172 - Powertrain System too Rich (bank 1) and a Pending fault of P0170 - Powertrain, Fuel Trim (Bank 1). I don't know 100% if this is the root of my problem but any help would be appreciated. I thought maybe a clogged cat, but I haven't had the chance to get the car up and check. Any help as of always is appreciated.

 

Did you use the BG44k as instructed ? Could of used too much