I have a 94 Del Sol S that had an engine swap done about 4 months ago and a Greddy Exhaust installed. Now I have a B16A and it was running fine until few days ago.

1. When I rev the car it starts to rattle violently. The car still goes, doesn't stall and rides. Eats up tons of gas and can't seem to fix any of these problems.
2. I replaced the spark plugs and found that in the 2nd cylinder the spark plug looked like it had some carbon fouling. I check the wires and the cap and rotor and swapped everything except the rotor because it looked fine. This help the problem just a bit.
3. What I ended up with is a car that revs fine when you barely push the accelerator, but when you push is at somewhat normal throttle, the symptoms come back. Is this a clutch problem, or blown cylinder, or ....

Need some help.

Thanks.

 

are you throwing any codes? i would look into the type of gas you are putting in and think about replacing the o2 sensor.