Valve Cover Gasket / Power Problem

Hi, I had the valve cover gasket replaced on my 3.4L Alero and since then I have had power problem. The pedal seems 'soft' and the car doesn't have as much punch has it used to. I took it back to the GM dealer where I had it repaired, but they say they can't find anything wrong. The pedal sure doesn't feel like it used to, it's soft. You know, if you touch the pedal on the 3,4L, the car just punches forward. It seems I have a loss of power, soft pedal or loss of compression. I am not a mechanic and know little about motors. Do you have a clue and suggestion for me please. Thank you very much.

Well, check for oil leaks and find out if you can smell oil burning. Valve cover leak wouldn't cause that extreme of a power loss. Check your PCV valve. I would start there. It's a little plug-looking valve that is on your front valve cover. You can't miss. Pull it out, shake it a little bit. You should be able to hear a little rattle. If you can't hear the rattle, have that replaced. It's only about $3. While they were changing out the gasket, some oil could have gotten in there, plugging it up.
Check your connectors around the engine. They could have overlooked something and forgot to plug it in. When I replaced my Lower Intake Manifold gasket, I replaced the valve cover gasket too and the back cover has alot of electronics around it which you have to remove to get to it so they might have messed something up.
Otherwise, something else in your car is going wrong coincidentally and have really nothing to do with changing out the valve cover.
Just curious, what kind of sound does your engine make? If I heard it, I would know better, but obviously, I can't. Good luck, dude.

Coincidently it does smell like something is burning, smells like oil. The engine is quiet, a bit of rattling sound like a diesel engine would make. I will take it to another dealer for a second opinion and also tell them about the smell. I hate loosing gusto and not knowing what is wrong.

[MilzyZ34]

check the throttle cable bracket, make sure the cable is seated properly