Ive been breaking in my new D series motor that i built and all of a sudden the motor doesnt seem like its firing correctly. It will idle great and it will rev good when not moving, but once i start driving it starts sounding like a lawnmower or like its missing a little bit but i cant see to find out whats wrong with the damn thing. Its getting tuned with Turboedit FYI. Another scenario is when i floor it, the motor will rev really slow, but when i give it about 40% throttle it revs as it should. All of this just suddenly happened one morning when i woke up. It also seemed to coordinate with getting some gas from a new gas station in the area. Mainly the problem is when the car is under load, it doesnt seem to respond well to throttle changes. FYI it was running fine the first day i started it, it ran like a normal car.

 

timings off

 

it doesnt seem to be the timing because the motor was running on the same program for a week and it was fine, now the motor is acting like its misfiring under load. It sounds like its dropping a cylinder.

 

Check your spark plug wires.

 

i would do like the others say id check your plug wires and plugs id also check the timing out anyway. the timing belt doesnt care what program you ran week ago if its loose it will slip and if it does slip you may have bent a vavle or vavles also check your wiring at the coil to make nothing came loose your is loose