92 stalling from erratic idle and at highway speeds

Hello everyone this is my first post in this forum, but I've been reading all the threads for the past few weeks.

Here's what's happening I just purchased this "92 trans sport gt" from a local mechanic who sold it for $300 Cd, just to get what he had into it. He told me that there was an electrical drain on the battery and it needed a new front windshield wiper motor and a windshield to pass a safety.

I've owned a "90 trans sport se" for the last 2 1/2 years with very few problems, (TCC SENSOR, BALL JOINTS X 3, FRONT BRAKES, CATTALYTIC CONVERTOR) and knew that the 3.8 L engine and 4 speed transmission would be a nice upgrade.

We started the vehicle after it was sitting in the snow for the last 6 months with no problems. I noticed that after driving it a bit the idle would vary from 500 rpm - 1000 rpm and stall if I didn't give it gas. I searched the forums and thought it might be my EGR valve.

I've replaced the battery because I assumed that the original was frozen from sitting all winter with out a charge. I noticed that the front and rear wipers work along with the pumps, which is a bonus.

What I noticed wasn't working was the AIR COMPRESSOR, A/C, REAR BLOWER (which has 2 control switches), CRUISE CONTROL, PASSENGER SIDE WINDOW working when it wants to, and the issue with the erratic idle (sometimes). I thought that the stalling problem was just at idle, but I found out the hard way that it also happens while driving at highway speeds. The motor would just die than start running again while cruising down the highway until it died and wouldn't start. I had to leave it sit for a few minutes than it would start again and allow me to travel any where from 5 meters to a few kilometers before it would die again.

The engine light came on so I read the codes when I got home and it had a 17, and 18.

17 - was spark reference circuit
18 - cam/crank error

so which sensor should I change, the cam position sensor or the crank position sensor? and where are they located?

The crankshaft position sensor is a very common issue, so in all probabilities, this is the one to consider. The cam position sensor in fact just informs the INJECTION system about when to inject fuel. It does not have an effect on the firing that occurs on every turn anyway regardless if the piston is on the exhaust or the compression stroke.

www.avigex.ca/xport/ckps.jpg
www.avigex.ca/xport/ckpulley.jpg
www.avigex.ca/xport/ckpsremoval.jpg
www.avigex.ca/xport/dtc17.jpg
www.avigex.ca/xport/dtc18.jpg

thanks for the info, LMP I ordered the crankshaft position sensor from Canadian Tire this morning $45.99 Cd. I'll post back with my results in a few days. One question, I noticed on the ckpully link that you need a "torque angle meter", what do you use it for and how? thanks.

I do not think it is necessary...several on this forum did the job successfully without this contraption.