My 1983 944 Won't Start

[RonLoeff]

I Seem To Have The Same Problem As A Few Other People Here. No Spark From Coil All Of A Sudden. A Few Articles Point To Sensors. In Particular The "Reference Mark Sensor" But, I Don't Know Where This Sensor Is To Clean It. Can Anyone Tell Me Where It's Located And Any Other Sensor And Location That Should Be Cleaned Or Checked? Thanks.

[drew1]

Ron,

There are two sensors, they are identical except for label on the wire if it's still there. They look & function kind of like proximity switches used on industrial machinery. These sensors are bolted down to a bracket that they go through, through the bell housing, where one senses teeth on the flywheel and the other a set screw on the flywheel. I believe the one that counts teeth is the speed sensor, labeled DG, and the one that senses the set screw is the reference sensor, labeled BG. If the heater hose and valve is in the way, you're getting in the right place to get these out. You can pull the sensors without pulling the bracket.

The sensors are magnetic & if iron dust gets on them they might not sense the seet screw or ring gear teeth correctly. In the 3 terminal plugs:
between the inside sensor wire and the outside you should ohm .6 to 1.6 Kohms. Between a wire and the sheild, other outside terminal, you should get more than 1 meg ohm. On the two wires on the speed sensor you should get a small AC volts reading while cranking.

One thing I think you ought to check on this car is the fuel pump relay. Check the fuse , #2 on the panel by light switch. Ref: 9 pin plug on fire wall. If its good you should be able to measure battery voltage between pin 2 red/blue wire and ground, and measure bat volts between pin 3 red/yellow and ground. With the nine pin plug undone & switch on, you should be able to ground pin 5 black/green and the pump run. If this is good your FP relay is OK.

drew1

[T86951]

maybe a bad coil. Have you checked to see if you are getting voltage to your coil. If you are and no spark out of it then the coil may be bad. The Haynes manual has volt and ohm tests for the coil. If you don't have the spec/s I have a manual and can look them up for u.