Have a 2001 monte carlo ss with about 160K. Drove it one night for about 150 miles came home and parked it. Went to get in to drive it the next day and it will get to about 2500rpm and lose all power. Just like it is bogging down. Step on accelerator and I can hear like a clicking noise under the hood. Temps have been -20's and 30's with windchill even worse but I have never had this issue at all with it or any other vehicle for that matter. If it is in park I can rev the motor with no issues what so ever. Thinking maybe cat converter but exhaust comes out and exhaust does not sound plugged at all. Any ideas? I live about 60 miles from any town in the middle of God's country so it is not very accessible to just drive it in to a mechanic. Check engine light is not on however my air filter was covered in ice and had some snow around it. Possible mass air flow sensor?? any suggestions appreciated. Thanks!

 

Wanted to mention that this is NOT the supercharged engine either. Not sure if that matters but wanted to be sure that was out there.

 

Even though exhaust is coming out, it still doesn't mean the cat is in good health. It was known in '01 GM had a run of cats that failed early. Your symptoms sound like they could be cat related. If so, when the car has a loss of power, check under it and look at the cat. If the cat is really clogged, it will probably glow red due to the heat. If this is the case, I would definitely STOP driving until it has been serviced.

As far as the air filter being covered in ice, are you talking about the black plastic air filter box OR the filter itself? If the filter itself was covered in ice (the actual pleated filter element), yes, this will cause problems, as the ice will stop the filter from allowing air to travel. The car is unable to suck air in and is basically choking. If this was the case, replace the filter, as that much ice and later water is not doing the filter any favors. You should also try to figure out how it iced up in the first place.

Lastly, if neither of those are the issue, I recommend you look at the thread I linked to below. Some of the items listed in it (like spark plugs), if they have not been done could be part of the problem:
https://montecarloforum.com/forum/ge...0-miles-46078/

 

I blew out my catalytic convertor last week. I used it an excuse to get rid of the ubend by getting a ZZ Performance downpipe with cat. I think if I changed oxygen front sensors first I might have saved some money. Definitely change both O2's if you change the cat. Go to autozone or advanced auto and get a diagnostic and find out what's wrong before spending money throwing parts at it as I did.