I have had my Buick for about a year. In May I had my ac pump blow and and to replace it. When this happened my check engine light came on and my cruise control stopped working. Everything else continued to work fine and due the the odd nature of the obd sensors my mechanic couldn’t actually read or clear the computer. I did not have any issues till recently, ever since the weather got cold(it’* Pennsylvaina) my car has been acting funny. About a month ago I had lost almost all power while driving it and it started idling rough. I had added oil to the car and got the power back(had to put in 4quarts, but no signs of a leak) I then had put some type of fuel injector cleaner in the gas tank with some high octane gas and for the most part the idle issue stopped. I started my car after work the other day and it was doing a jerking thing, like it wasn’t getting a steady stream of gas? I stopped and checked my fluids and had placed another quart of oil. Started it back up and it was fine. I went to drive it last night and it did the same thing but worse. It was jerking and really bad usually when I would put it in drive and start going it would calm down to normal. This time it didn’t. I am at a lost for what is going on with it. Can anyone help?

With no visible oil leaks and the amount of oil you're going through you may have a clogged catalytic converter and/or fouled spark plugs. You could start by pulling a spark plug on the front cylinder bank (easiest to get to, the one facing the radiator) to check for fouling. I believe 95 was the transition year of OBD, so you'll want to find someone with or buy a scanner capable of reading OBD 1.5 codes to see what'* causing your issues, but if you plan on keeping this vehicle you're going to have to address the oil consumption issue or you will end up like a dog chasing it'* tail.

thank you, I will start by checking this stuff out.

Car runs bad, he adds oil, and it'* a miracle?

First thing you better do, is find that oil leak...the fact you added 4 quarts and your car takes 5 should tell you something....and that something is not to just add oil....if not an external leak, I would be checking two things under your valve cover....clean return holes for the oil, and valve stem seals.....I have seen the metal rings around the seals break, causing the seals to leak....another source is the oil rings on the pistons, but that would be very rare on this engine...

garagerog is kind of on track...the oil could be fouling the plugs, your O2 sensor, etc. Knowing the exact codes would be a huge help....

What bugs me though is, you do not mention, any blue smoke from your exhaust......to be burning up that much oil in a cylinder, you should be smoking up the house like my father did...of course, he did that with cigarettes....

Are you absolutely sure there is not an external leak?

One more question...ok, two.... how many miles on the vehicle? And are you doing your regular maintenance to it?