i have a 2000 nissan maxima SE. its about 124k miles deep. recently developed a symptom. after driving for about 10-15 minutes i notice a vibration when trying to accelerate. it starts right around 40mph and doesnt stop until i park the car for a good amount of time. can anyone give any suggestions as to what this might be?

 

Little vague, so I'll answer as such.

Do you have an SES light.

If so, get the code.

Local Auto store should be able to check the code.

Once you get the code, post it on here and do a search for it.

 

these are the codes the SES light threw P0430 and P0304

 

My assumption would be the 0430 is a failed/(ing) pre-cat in bank #1 and the 0304 is a Cyl #4 misfre.

It's possible that the latter may have caused the former and a misfire will cause a shaking/misfire type of feel.

I would remove the coil pack in #4 and move it to another cylinder and see if a new code pops up, if so, you need a new coil pack. This is the coil in the center of the front bank, basically when you open the hood, it's staring right at you.

If the spark plug looks like it's in bad shape, replace it, and probably all since odds are they all look as bad if not worse, do all 6.

What year is your car?

 

Its a 2000. funny thing is, i just replaced all 6 coils and plugs over the summer as per the suggestion of my local dealership. cant seem to understand why that could cause a problem anymore. in anycase, i dropped it off for a local mechanic who replaced the plug in cyl #4. the shaky feeling is still there, and the SES light is still on.