Car battery went dead recharged, and car only wants to start once in a while, this was a new battery six months ago 2oo5 buick lacross csx

That happens usually when battery is dead . Check connections again also check voltage on battery may need a charge . You said you cleaned your batt terminals corroded terminals is a sign of a leaky battery

this link will show location and replacement proceedure How to replace PCV valve on GM 3 8L 6

Have an auto electrician check out the wiring of the car. there could be a short somewhere in the wiring

Pur hot water over the conections, and then spray it whit a WD-40 or something on the terminals; try with a battery charge.

u gotta get a fresh new battery for ur buick. how old is the current one ?

The cap on the positive battery cable can be pulling out and it has a thearther to not lose it. Some on them have two battery cables and their well known to get corrosion under the bolts and bewteen the cables and the side of the battery the bolt head is 5/16 or 8 MM and needs to be taken apart and all cleaned and connected it's best to charge a low battery or change it as the altenator can go up in smoke after a few minutes charging a dead or low battery after a jump start. If nessary connect the jumper car with it running and let it sit there charging for awhile, then start the dead car and still leave it connected to stableize the charge and not ruin either car. Once running take the car to a parts store or service center and have them test the battery and the charging system. You can aquire a battery charger if you can get an extion cord to the car and charge the battery and in a few hours the car will start if the battery is any good and the charger works correctly. If the battery is real cold and real dead it's possible the battery can explode if jumped off wrong or making a spark. Be real careful with low and dead batteries as they can spray acid in your eyes and on your skin and sparping lots of water on yourself in the cold is a bad deal. and lots of water is the only good way to deal with the acid.

No a Plugged fuel filter would not cause more fuel consumption but would lead to damage to the injectors and the fuel pump, and is much cheeper than the fuel pump or injectors. And I believe you mean Flex plate broke? And I do believe you should check with the dealer this unit should have a 100,000 drive train warrenty and they should kick in on the transmisson.

may just be a loose terminal. I had mine replaced and it took a few hours before it ran right again. something about the electronic modules take a little time to recharge.

Could be both batteries went bad.
1) I would take battery back to where you bought it and have them test.
2) Check, or have someone check, that battery power is not being used when the key is off and the car is not being used in any way. There will be a slight trickle of power use, but nothing that would wear the battery down in less than 3-4 weeks.

possibly the alternator. or even a bad connection on one of the wires