I don't know what's wrong.....

[20Bonneville00]

I'll just get right to it. Say i'm driving on the highway and I want to speed up a little. I press the gas a little but instead of the engine rpms going up like you would expect, it seems like it gets bogged down. Now I'd assume that at that point it would down shift and kick up the rpms but that doesn't happen unless I push the gas farther in. Is it possible that I'm missing a gear when downshifting? because once I get it to down shift I have more than plenty of power. BTW there is also some slight vibrations that come when it's "bogging" down. I really have no clue what is going on any help is appreciated.

[Franksdad]

clogged catalytic converter? im just guessing because this wasnt the greatest description. try banging the cat with a wrench she if it sound like broken stuff in there lol dont bang too hard or you may break it

[bobgto65]

It may be a clogged convertor but my transmission problem first came up under light acceleration especially from 4th gear, but it was more of a surging and not bogging down.

[20Bonneville00]

If it was the converter wouldn't that make the engine run bad at idle and other times? not just when i'm going down the highway?

And it actually is surging a slight amount. it's like it want to work right but it can't.

[spoiledred94]

Hey, I'd like to jump in, if I may.
My car does the very same thing and I'm also getting a bad CAT efficiency P0420 DIC. And I have a CAT rattle. And I get the same vibration too. I always feel it in the accelerator pedal. I start getting bogged down in 4th (I think) when cruising at low rpm 45-60mph and if I get to WOT fast enough it might down shift-maybe not. I/ve just been assuming my transmission itself was failing.

EDIT:

Oh and I have lost some acceleration and power too over the last year.

[20Bonneville00]

So I've also noticed that I have a pretty substantial loss of power when I'm at lower rpm's. And sometimes it is rough at idle. However, I just traveled 250 miles back from college and I averaged about 26ish mpgs..... Anyone have any suggestions on what it could be? On a side note, I did my lim gaskets and other little things over thanksgiving break. Could there be something that I could have done wrong?

[macksdaddy77]

is your cat glowing?? it rly seems like the converter