my car just shuts off while driving.
You can just be driving down the road and my 1991 lexis will shut off. after it
set for a while it will restart and run for a random amount of time. What could
You need to find out if it is spark or fuel that quits working, the draw back is you have to get it in failure to do this, when it is in failure just spray some starter fluid in the air intake, if it starts and runs briefly it is fuel, possible fuel pump or relay, fuel pumps are the most common, if it doesn't then it is spark, possible ignition module or coil, modules are the most common failure. HTH
One possible cause is loose or dirty ground contacts. This can cause the exact problem you're having, as it has for me, especially with older cars...and it's not a comfortable situation to be in. In my situation, the ground contacts from the (-) battery post to the frame were heavily corroded and dirty. Disconnect it, give it a good scrub with a wire brush, use some battery grease where the cable contacts the metal and tighten it back to the frame. Free fix, and just good to check out anyway...could be all you need!
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