Thanks for the tips, I will be checking my pvc, coils and wires this afternoon. My stuttering/bucking only occurs under light acceleration on the highway. My idle appears to be fine.

Where is the trans vacuum modulator? I'd like to put my hand pump on it and check it too.

Thanks, Tom

The module is on the trans itself, on the front side. looks like a can with a vacuum line going to the front of it. You can buy an adjustable shift module for around $20 at some of the parts stores. But make sure this is the problem first before you install it.

When you guys did plugs, did you change wires? If they aren't good quality wires and don't look new, there is a chance of the wires being bad as well.

Also, please ensure that the #4 and #6 cylinder wires aren't touching the O2 or it'* wiring. That can give the car a case of heartburn. =0)

Check coils, plug wires and vacuum modulator. Everything seems ok. The boots connecting the vacuum lines to the press reg, canister and vacuum modulator were all cracked (unsure if before I pulled them or as a result, but they were very brittle) so I will replace those today and continue troubleshooting. Thanks, Tom

I replaced my vacuum lines and I still have the same problem. The "bucking" seems to take place at 40mph or above, light acceleration. My guess is transmission, no engine codes. It reminds me when driving a standard transmission and upshifting and accidently skipping two gears (shifting from 2nd to 3rd, accidently going into 5th my missing 3rd). Any suggestions will be helpful. Thanks, Tom

Have you checked your crankshaft sensor? Sorry if I asked that already.

I have not. Can that be checked or do I just replace it? I think I saw the procedure for replacing in the technical section.

I'm writing up a test procedure right now.

With the engine cranking, check the voltage from the orange wire to ground on the crankshaft timing sensor and the camshaft reference sensor.

• Over 7V is satisfactory.

With the ignition switch on, check the voltage drop across the ground circuit (black/light blue wire) on the crankshaft timing sensor and the camshaft reference sensor.

• A reading below 0.2V is satisfactory.

When using a digital voltmeter to check a crankshaft or camshaft sensor signal, crank the engine a very small amount at a time and observe the voltmeter. The voltmeter reading should cycle from almost 0 volts to a highter voltage of about 5 volts. Since digital voltmeters do not react instantly, it is difficult to see the change in voltmeter reading if the engine is cranked continually.

• If the voltage does not cycle, sensor replacement is required.

• Each sensor voltage signal should cycle from low voltage to high voltage as the engine is cranked.

Hope this helps. Kind of whipped this out fast

Hi Dan, Thanks for "cranking" the procedure out. I will try it out, hopefully in the next day or two. Do I get to the sensors from the bottom or top side? What is strange is that my symptoms only occur at higher speeds and under lite acceleration. Really feels like a tranny, but my hunches are usually wrong.