I have a 2003 Monte with 150,000 miles and recently just got over $5,000 in parts and labor work done. It didn't do this before but since I got it back it has. When I floor it, the acceleration is weird. It's not a smooth acceleration into all gears, (shifts fine though) before the shifts its as if its puttering. Some of the work I got done includes head gaskets, alternator, water pump, new hoses and belts as well as tranny filter, tranny pan and a few other things.

Just seeing if anyone else had this problem before and knows what it is or what it sounds like. It almost feels like the engine isn't getting enough gas when I accelerate idk what it could be but it bugs me when I try and show off

 

Cleaned the MAF lately? New plugs and wires? Possibly coil packs as well. Could be a number of things lol.. I noticed a difference after changing plugs and cleaning my throttle body for the first time. (I was having a similar issue, lack of acceleration).

 

+1 to 01 Monte SS. My gusband use to have an 02 SS that did the same thing. We took out my MAF and drove his car to Lodi and back no issues. They make a special spray cleaner for the MAF. Brand new MAF is about $150 life time warrenty also.

 

Clogged cat? I had basically the same symptoms that you're talking about with my 03 a few years ago and it ended up being a clogged catalytic converter. The car felt like it had almost no power when I would accelerate. It wouldn't always shift at the shift points, mostly from first to second. It would just high rev and I'd have to let off the accelerator for it to shift. Gradually got worse over time. I thought I had some serious problem but it was just the cat. Dealership replaced it and performance was back to normal after.

 

X2 A clogged cat could do it too!

Did you try cleaning the maf at all?

 

When I first bought my 2001 Monte SS Pace car it would have very poor acceleration.
Took forever to get up to speed, no power.
Come to find out ? it needed a new engine mount.
Now it has pep and zip.
Check your engine mounts.

 

My 2nd Monte has the same problem, yes, I have 2 Monte Carlos. one if a pace car and the other is a plain Jane LS.
I would push on the gas and the throttle uses to stick so I cleaned the throttle body when I discovered that my fuel regulator was leaking.
So I figured I might as well clean the trottle body while I have it off and it was caked with crud and carbon.
The throttle body does not stick anymore.
However ?
My Pace car did the same thing when I first got it and come to find out ?
It was the engine mount.
Yes, right after I replaced the engine mount it had zip and pep now.
Even if the hydro engine mount looks ok ? it could be internally collapsed inside.
The metal pin on my old engine mount was bend also.
Everyone who has this problem ? check your engine mounts before you spend $ hundreds of dollars on other parts or a new cat.

 

The cleaner is called Mass Airflow Sensor cleaner.
Anyone who is going to try and clean their MAF sensors ? caution please ?
Please do not use any other cleaner other than MAF cleaner or you can damage it.
I know the cleaner for that can get expensive but it's better than buying a whole new MAF sensor for over $ 100