engine light code: crankshaft timing is off

Does this sound right to you guys? The car runs absolutely fine except for one thing. While getting on the highway at about 50mph or so, the rpms dip to about 1800 rpm for a split second then back up to about 4000 rpm. Do you think these two problems are related in some way? I imagine that the engine light really refers to a sensor for the crankshaft. Is this an easy fix for someone? Thanks in advance for any advice.

My '01 with 4.0 V-8 had the same symptom as yours, and it also stalled at low speeds or stoplights. I replaced both crankshaft position sensors and both symptoms disappeared. If you have a Classic, I'm not sure if they had one or two CPS's.

The pair of sensors cost $70 from www.gmpartsdirect.com

Changing them (front center of engine, remove splash shield below radiator and do the job from beneath the car) might have taken less than an hour if I didn't have such large hands and forearms - - tight access made it a 3 hour job for me.

I just want to say that I am an idiot... I forgot to mention that I have an '01 with the V8 also.

So will I see the sensors when I take off the splash gaurd? Or will I have to dig into it a little further?

You will be able to see the electrical connectors and the sensors ......front center of the engine block. But things are pretty tight and you need to be careful with the connectors when you remove them.

10mm socket, rachet, extensions, and a swivel are the only tools you need - - oh yeah, I used a screwdriver and pliers to remove the plastic clips that hold the splash shield on.