I have 70,000 on my 2004 mazda 3 and it seems like its falling apart. barely 6 months ago I had to get a new fuel pump because the engine would crank, but not start on the first try. That cost me $900. Now I get a knocking noise when idling. From the sound I thought it was the timing belt, but its they diagnosed it and said it is intake assembly that needs to be replaced. And it will cost $1500.

That is a lot of money on a 5 year old car. Any recommendations on this new problem? Is it necessary to replace the intake assembly? I had it running like that for a few months now.