'93 Camry LE v6 3.0 Studdering @ 40-50mph, Rough Running
 

I picked this car up mainly due to the low miles (99,xxx) and the fact its a V6. Well it ran like absolute garbage when i got it, i knew it needed a tuneup at the least.

i replaced the plugs and wires with NGK, double checked the gap on the plugs as well. Replaced air filter, fuel filter, distributor, cap & rotar. It made a difference for sure but i am still having some issues.

The first being that if you are at roughly 1/3 throttle and going somewhere between 40 and 50 mph, it has a studder that rattles the whole car. Oddly enough, if you go 1/2 or more, or less than 1/3 throttle (lightly pressing it), the studder doesnt happen?

The car also runs rough, especially when cold. I have taken it to two mechanics who cant figure it out and are calling some Toyota technicians for help. THey said they may not hear back for a week or so.

All fluids are good. It sort of sounds like there is a miss but i cant track it down. The cat converter is also basically new as i can see daylight through it.

Stick or automatic trans?

Was the ign coil replaced?

Ignition coil has not been changed and it is an automatic.

Try to determine if the "studder" is related to the engine or trans. A bad torque converter can cause the car to shake.

Check spark. Should be white or blue and able to gap one inch.

Check coil for cracks and signs of arching.