Camshaft or Crankshaft Sensor?

I have a 98 Chevy K1500 that just started running rough but not all the time. The check engine light came on today so I stopped by Autozone and let them pull the codes. It showed multiple missfires on all 8 cylinders. The guy there told me that it was either the crankshaft sensor or the camshaft sensor. I've got fairly new wires,plugs,rotor and cap (all replaced within the last 2 years). The truck has 130,000 on it. Any ideas ??:banghead:

The timing on that engine can only be set with a scan tool. If the dist was moved, it needs to be set properly. The dist gear can also wear and cause misfires.

Before you blame the cam position sensor, make sure the gear and upper dist bushing are good.

Inspect the inside of the cap, if there is heavy corrosion or moisture, the vents could be clogged.

//2000CAYukon

The timing on that engine can only be set with a scan tool. If the dist was moved, it needs to be set properly. The dist gear can also wear and cause misfires.

Before you blame the cam position sensor, make sure the gear and upper dist bushing are good.

Inspect the inside of the cap, if there is heavy corrosion or moisture, the vents could be clogged.

//2000CAYukon
Thanks for the info. I'll check those areas first. I also read in my Chiltons book that the camshaft sensor does not affect the driveability of the truck it only notifies the computer of misfires. Is this true? I've been told that they do affect the running of the motor.

There are plenty of threads in this forum (one of them mine) where a camshaft sensor caused rough running and misfire codes. It's easy to replace and fairly cheap ($50 or so and about an hour of labor). If you have any suspicions, go for it. The crankshaft sensor is about the same price and much easier to replace. You can have them both replaced in 2 hours and less than $100. I'd also double check the wires, plugs, rotor, and cap because any of those could be causing the same problem.