Help a newbie -- 95V6 shakes and knocks

I have a 95V6 convertible with 105,xxx miles on it...the car seems to be shaking as of late, and I couldn't tell if it was the engine or the suspension/tires/alignment, etc. It was minor for the most part, but I could notice the passenger seat shaking when I was driving and nobody was in it. Now, sometimes when I climb a hill and am accelerating, it will start to knock for a short period of time. Here are some other symptoms:

Sometimes when I fire the engine, and put it into drive (automatic), it will sqwak the tires without me even getting on the gas (pretty impressive since it's an old V6) (kinda rare)
Sometimes when I accelerate, it will hesitate a bit, and then go
At certain RPMs (low) sometimes the engine just seems to be sluggish
My gas mileage has been steadily falling. I'm getting about 260-275 on a 15 gallon tank...I've been using the AC and sitting in some traffic which I'm sure doesn't help, but...
No "check engine" lights are on
I've had the head gaskets replaced awhile ago (around 88K miles) -- temp is running fine and OIL PRESSURE is good (please tell me this eliminates rod knock)
I ALWAYS use 87 octane fuel -- as the car is getting older, does it need 89?
Think she's due for spark plugs or O2 sensors? If so, can you tell me the model numbers and how many O2 sensors my 95V6 would use?
I changed the fuel filter around 95K and the cam position sensor (or something like that) about a year ago.

Whatever thoughts you can share are MUCH appreciated!! I'm getting married and buying a house soon and I can't afford my car to **** out on me!

Thanks.

Please help!!!!

Hey, thanks much for the reply...I see it says you are located in TN, but your handle says ATL...you a former Georgian?

I don't think it's my head gaskets acting up again....I had tale tell signs back then...temp would always be REALLY warm, even in cool weather...and my heater didn't blow hot air.

There are no fluids beneath my car, and I don't smell coolant. All my fluid levels seem to be good. I've put 28K miles on it since I bought it used and haven't changed the plugs yet, so I'm sure it is due. Also, don't most O2 sensors start crapping out around 100K miles? It would explain my falling gas mileage...and dirty plugs and O2 sensors might cover the sluggishness...and HOPEFULLY, that is responsible for the knock...

Mind you, the knock is VERY infrequent, just for a short spurt, and ONLY when I'm climbing hills it seems...the vibration is also pretty minor.

When I heard the knock, my fiance heard it and said that is what she heard while she was driving her car before the engine killed (granted, she drove it like that for a whole MILE...mine lasted about 2 seconds...and it only happens once every few days or so.

Think O2 and plugs are a good place to start? And again, anybody know how many sensors a 95LX would use? And what plugs are good? I've heard Autolite, but I don't know the exact model #...

Thanks again for your thoughts, blue.

Any thoughts on the knock? Please tell me it is nothing serious.....

I know this was a year ago, and probably nobody cares, but it just had a spark plug fork that was busted. When they installed new spark plugs, they tightened them down too hard.

Skymarshal said:

Check your tranny fluid. Is it topped off, and does it look clean and clear?

Most of this sounds like it could be caused by dirty, gummy tranny fluid. As long as the tranny itself is in good shape, you could get away with doing a flush and fluid/filter replacement at a tranny shop.

Click to expand...

It was a busted/burned off fork on a spark plug (see above).