Over the holidays my car got a new radiator, heater core, plugs, wires, pcv valve, water pump, and thermostat. I also unfucked my exhaust rattle. It runs much better than it used too except that now at 50mph under slight throttle the car bucks back and forth rather violently. It almost feels as if the engine is bogging down but the RPMs don't reflect that. The only thing that comes into my mind is maybe the drive shaft.

I also believe I have a loose rocker because of a fairly loud tick (can be heard over my exhaust) that increases with engine speed, especially under load.

It also has the noisiest ******* alternator known to man.

Any insight would be much appreciated.

 

It kind of sounds like you might have a clogged catalytic converter.

 

Wouldn't that be noticeable all the time, not just at 50 mph? By the way the car has 102,000 miles on it.

 

Does the vibration change with engine speed? Transmission gear selection?

 

I Strongly believe you may have a misfire issue. The air blowing around in your engine compartment is causing the wires to arc off of something. Got headers? Could be that. Take a few minutes to look around under there.

 

I'm sure of it. Just cause the check engine light dont come on dont mean anything. I had miltiple cylinders missing before the SES light lit.

 

Thanks, I'll check it out tonight if its not negative ******* freezing outside. Any other thoughts?

 

Just took a good look, no arcing, so does that mean a bad plug? I unplugged my maf earlier and drove around but didn't get a chance to go past 30 mph, it did run a little smoother.