'97 3.3V6 juddering and knocking
 

Just hit the 101K miles mark, and the car is starting to seriously judder, especially around 1.5-2K revs.

I think it's just the plugs, as they've never been changed.

However, going up hill a bit, there is a loud knocking noise comming from the front middle. Sounds like the engine mounts, but you can't feel anything when it knocks.

Any ideas?

Thanks guys!

It can be the lockup. I had that in my grand Voyager 3,8 V6 automatic trans from time to time, aspesually in uphill in low rev, just like you said. I solve the problem with goingfrom D to 3 (no overdrive) on those hills, but I knoew it's a common problem with overdrive, it gets hot....

Try changing tranny oil. The oil shall be red, nor orange or light brown. And chenge filter as well...

I don't know about changing trusters in the tranny... anyone done that?

Hi thanks for that.

I don't think it's an OD lockup as it does it in all gears and now does it at idle.

There is however a serious knocking noise, deffinetly metallic happening, apparently worse in the morning. It is deffinetly metallic, and it also knocks with the revs, but up hill it's a really bad knock and you can feel it through the pedals.

did u spin a bearing or something? rocker needs adjusting?

I don't think so. The metalic knocking I've discovered is something to do with the aux. belt.

There is a firework noise comming from the exhaust manifold we think. Seems like unburnt fuel is igniting in there.

MPG is very poor as well.

if the knocking is coming from the accesory then make sure all the brackets are tight

as for the MPG issue: try seafoam (an engine detergent and treatment fluid) for more info on that do some research online. but anyway u should probably dump a 1/2 can of seafoam in your gas tank and this will make the whole fuel system squeaky clean as well as clean some carbon out of the engine cylinders