I have two 1990 SC's, one 35th anniversary edition with 60k miles and a silver one I have from new with 135k miles, both automatics. I purchased the 35th anniversary edition with 56k miles a few years ago. Many years ago at 62k miles, the silver one gave the Ford dealer fits and took about a week to repair the bucking ignition. I asked the mechanic what the problem was and he mumbled something about the crankshaft sensor. I changed the plug wires and plugs on the silver one at 120k miles and in a matter of months the bucking started again. The result was poor quality plug wires after having gone through the sensors and DIS again.
Now my 35th anniversary edition has started bucking at 60k miles. The engine is basically untouched as supplied from the factory. The engine starts bucking bad and the tach goes to zero after driving a few miles. It bucks so hard you cannot accelerate but only slip it into neutral and goose it until it smooths out a bit. I figured the loss of tach would be caused by the DIS since it sends a PIP signal to the computer and and camshaft sensor. I changed the DIS and it ran worse, taking three tries to get it started. I ran it for about 5 miles and the bucking came back. I cleaned the original Ford DIS, used liberal heat sink compound and reinstalled it. I also inspected all the pins in the DIS connectors for any corrosion and they looked fine. I also pulled the crankshaft sensor plug apart and inspected it for corrosion and it also looked good. I took a small pin file and scratched around each male pin and scratched the entry on the female pins to insure better contact. I assembled the plug back together and the car runs fine at least for the 15 miles I drove it so far. I'm still at the point where I don't trust this thing. I also did a scan and a code 19 is in memory which is listed as cylinder ID fault.
My question is how do we insure good connections in our sensor plugs where very low level(Current) signals are likely to have connection failures. A plastic plug heating and cooling over time can cause movement that can damage the connection over time. By just replacing sensors are we just freshening up the connections or have the sensors truly failed?
These ignition problems are a pain. I swear I've seen more dependable ignition systems in lawn mowers.
Now my 35th anniversary edition has started bucking at 60k miles. The engine is basically untouched as supplied from the factory. The engine starts bucking bad and the tach goes to zero after driving a few miles. It bucks so hard you cannot accelerate but only slip it into neutral and goose it until it smooths out a bit. I figured the loss of tach would be caused by the DIS since it sends a PIP signal to the computer and and camshaft sensor. I changed the DIS and it ran worse, taking three tries to get it started. I ran it for about 5 miles and the bucking came back. I cleaned the original Ford DIS, used liberal heat sink compound and reinstalled it. I also inspected all the pins in the DIS connectors for any corrosion and they looked fine. I also pulled the crankshaft sensor plug apart and inspected it for corrosion and it also looked good. I took a small pin file and scratched around each male pin and scratched the entry on the female pins to insure better contact. I assembled the plug back together and the car runs fine at least for the 15 miles I drove it so far. I'm still at the point where I don't trust this thing. I also did a scan and a code 19 is in memory which is listed as cylinder ID fault.
My question is how do we insure good connections in our sensor plugs where very low level(Current) signals are likely to have connection failures. A plastic plug heating and cooling over time can cause movement that can damage the connection over time. By just replacing sensors are we just freshening up the connections or have the sensors truly failed?
These ignition problems are a pain. I swear I've seen more dependable ignition systems in lawn mowers.