I need help to find the location of the crank sensor for the 1986 century crank sensor. Also is there a coil sensor? And where is the brain located and can it be tested? Is there a site with pictures and instructions? Thanks Eric

Crankshaft Position Sensor on the 2.5L engine in your Buick should be located on the side of the block, retained by a single moutning screw. There should also be a Camshaft position sensor IF you do not have a distributor on the car, it would be located either in the timing cover, or the head/intake manifold. The ECM on that vehicle is located under the dash, passenger side and yes it can be tested. In order to test the vehicle with the "Check Engine" or "Service Engine Soon" light on, locate the ALDL (Assembly Line Data Link) connector under the driver's side dash. The two holes on the upper portion of the ALDL closest to the passenger's side (named Terminals A and B) place a paper clip in those two terminals, then turn the key to the "on" position. The "Check Engine" or "Service Engine Soon" light will blink the codes to you. Each code will blink 3 times, the first and last codes you will always see is a code-12 "single blink-long pause-double blink repeat". All the codes in the middle are your trouble codes. From there you can either consult your Vehicle Service Manual for the code definitions, or run by your local Auto Zone and ask them.

I need help to find the location of the crank sensor for the 1986 century crank sensor. Also is there a coil sensor? And where is the brain located and can it be tested? Is there a site with pictures and instructions?  Thanks Eric

Thankyou !!

No problem, and on your car, the camshaft position sensor IS the portion under the ignition module that sticks down into the engine.