96 2.7 falls flat on its face.

My dad has a 1996 Tacoma ext. cab 2.7L 4x4 with a manual trans and transfer case an 195k miles. Within the last 6 months it has had new spark plugs, wires, cap, rotor, air filter, and fuel filter.

The issue that he's having is that occasionally if falls flat on its face. Usually it only happens in first gear. And when it falls on it's face if you push the clutch in it will rev freely. However when it's under load it acts like it isn't getting enough fuel.

Any ideas?

Thanks,
Bill

 

Clean MAF, and check the throttle positions sensor with an ohm meter. It should have a steady change in resistance, no dead spots or jerky readings.