1999 Buick LeSabre - Stalling problems

jim8923

Having trouble with 1999 Buick LeSabre when you're going down the road it just shuts off may go for days without a problem or I can do it twice in the same day. Always fires right up even if you switch to neutral while you're coasting it'll start right up and run fine. I get no codes when I put the code reader on it. Don't believe it's a fuel problem because it starts immediately when you hit the switch. Thinking it must be a sensor but I'm not getting any codes for sensors. If it is the sensors are they just Parts I can buy and replace or must they be reprogrammed. Thanks for your time

imidazol97

How does it shut down? Does the tachometer drop immediately to zero indicating the ignition control module is not getting any spark control signal from the crankshaft position sensor? Could be a bad wire at the CPS or just an aged position sensor. Because it starts right back up, it doesn't sound like the typical CPS, which has weakened magnetic field which weakens with the heat and fails after the engine is hot, often really hot to fail. Then it has to cool to restart until it cools. those can be tested by throwing cold water on the CPS which sits right under the edge of the harmonic balancer.

If it seems to shut off after hitting a bump, that might be a worn contact in the ignition switch. That's NOT the key lock on the ignition. The switch is moved by a rod from the lock cylinder unit and the switch sits on top of the column just behind the instruments. The switch moves copper contacts against each other and eventually they can weaken or corrode and their contact isn't solid like when they were new.

Could be a battery wire as well. Does anything else lose power when the car drops off?