Car is '87 740 turbo, manual trans.

1. Running down the firewall top to bottom just to the right of the valve cover (as seen looking from the front end of the car to the rear) is a single wire, with a single spade plastic connector, its white with a red stripe. what is it and should it be connected all the time? BTW this wire connects to another wire of the same color/stripe pattern with the opposite end of the connector. Thats why im asking about it, if it were just the female end or the male end or whatever i would just leave it. but there are TWO white/red wires, and it looks like they are meant to go together, but i have no clue what they are for.

2. I think its quite common but i'd like to post before i order the part. The plastic piece on the bottom of my distributor that connects to the vehicle harness (distributor connector, for lack of a better term), wiggles around ALOT, so much so that in a certain position the car will apparently lose the hall sender's signal and stutter. Should i replace the plastic part? The distributor? The hall sensor? Or the Cap?

3. Where is the fog light relay? i have a diagram and apparently its not in the same spot as it is in the car.

Thanks!

 

1) I believe that turns your ac pump on and off
2) replace plastic part, and since your there the cap and rotor
3) as far as the relay I thought they were all located in the console, some times there sharing with other lights whats wrong with the lights

 

really? whats an a/c pump? because it does seem to enter the lower section of the firewall where a seemingly large vacuum tube enters that same grommet. i'll leave it disconnected as the a/c is inop anyway.

yeah i pulled the distributor out and the cap is cracked, rotor looks like but and the internal seal is leaking, so i picked up a grip of parts from fcp, even got the "fiber washers". should have a nice reliable dry distributor now.

yeah i'll look around a little more on the relay, i'd really like to have those fogs back. yellow wire going to the switch must be the one coming off the relay, or maybe the switch sends the signal to the relay. i dont know, i know that part of the dash is a nightmare.

 

Go to www.stepbystepvolvo.com and download "Replacing the Hall Sensor Cable." I, too, have a 1987 740, in turbo. Lots of info in the article. For instance, lots of oil on the Hall plug will degrade it and eventually fry the Hall sensor.