98 Pontiac Bonneville SE 3.8 L started bucking & jumping?

Plugs and wires are a good place to start. Might want to check coolant level and plugs for any signs of coolant. 3.8's are bad for the intake plenum to leak coolant into the cylinders and cause misfire. Good luck

It could be so many things nowdays it is best to take it somewhere and hook it up to the computers at auto zone or somewhere like that....it could be something as trivial as a sensor

edit: if the engine light is on they can tell you exactly what it is with the computer and it can save you a lot of time labor and money in the process

recomend preventitive maintenence you should do a tune up a fuel filter fuel injection service coolant flush radiator hoses egr service go to a good repair facility that has a Tech 2 and check for updates this will also help i do see this problem a lot where i work also check trans fluid this may help also i dont recomend

a dealership unless under waranty

before everything, you're able to greater desirable than possibly blow a head gasket earlier you're able to crack a head if the wear and tear replaced into performed on the same time as using. something of this nature that could desire to occure on the same time as the motor vehicle replaced into sitting on your driveway, could could be brought about via freezing. even however the engine block could in all probability crack earlier between the heads could. do away with the oil cap and consider for a frothy cream colored foam. That foam is water. additionally, examine your radiator for oil.

sounds like a fuel pump or filter. a fuel filter is recommended every 24 months or 30,000 miles when is the last time you had it changed. also check the gas cap to see if its venting.

when you got complete silence turn your key just about were it starts go back of car by fuel tank listen how healthy the pump sounds

Did you read the codes? could be alot of things.