Help!

My son’s Mazda Millenia has power for about 3 minutes of driving, then will only go 2mph. when you press on the gas it has a loud knocking noise, it sounds like its outside the engine(the noise) It was in the shop and they replaced the harmonic balancer but the problem is still there. The engine is the 2.3 supercharged miller cycle.

Did the shop happen to look at anything while it was in there? If you could elaborate on any possibilities that have been investigated that would be very helpful. Did they happen to check for a clogged exhaust system, for example? Did they scan the computer for codes? If so, what codes were present?

They said that because of the year of the car not many codes were available to them, one o2 sensor read high…Also they said the car was running rich, the plugs were all sooted up and they replaced those. As far as a plugged exhaust, I don’t think that was checked, but this condition occurred really fast. Car was running great then bad.

You may have to take it to the Mazda dealership, simply because so few independent mechanics have done anything more elaborate than oil changes on these unique Miller-Cycle engines. How much experience does your mechanic have with this type of engine?

I had never heard of one of these motors until this post and had to look it up. It looks like motor is completely dependent on the supercharger to run.

I think that VDCdriver is correct to take it to the dealership, unless you can find a specialist mechanic in the area.

Everything is expensive on this car, the starter cost was $344, harmonic balance was over $350, they put a used one on it to save me $$. I don’t have a Mazda dealership in town. I thought for sure someone has run into a similiar problem. Any one want to buy it?