Impala 3.8L

• Automatic transmission
• 93,000 miles

I bought this car new in Oct 2000. My wife started driving it in Nov 2004 at 75,000 miles. After 6 years of owning and just 2 weeks before the extended warranty expired the car suddenly wouldn't start one day. It just cranked and cranked.
Towed to the dealer twice (free with Onstar), but the car started there and no codes.
The problem continued. Most times it would eventually start.
Then it started stalling intermittently.
It seemed to happen when the engine was cold, like when first driven in the morning.
No codes again. The dealer could find nothing and replaced the ignition module and fuel pump under the extended warranty before it expired.

The same problems continued intermittently over the next 2 months. The stalling started happening more often and was dangerous and it was making the car undrivable.
Finally it stalled on the road and wouldn't start. It was towed again to the dealer (where it started) and they had it for 10 days but couldn't reproduce either problem.
I had spent countless hours researching the problems on the internet, and I suggested replacing the crank position sensor. The service manager didn't think that was the problem because the combination of the no-start and stalling problems don't point to that sensor.

Since I didn't have the car to drive anyway, I said to just replace the crank position sensor. That solved both problems and after almost 2 years later the problems haven't returned. If that did not fix the problems I would have had to get rid of the car.
The dealer did it for free because they had the car so long and the car was always serviced there, plus I also own a 2004 Impala LS which was serviced there too.

It has been said that electronics will/can be the downfall of the modern car and that is why it would be hard to trust any late model used car. A problem that doesn't set a DTC can be very difficult to find and fix.

This was a very frustrating problem, especially since I wanted to keep the car and eventually pass it on to a child, so I had paid for all maintenance to be done above what Chevy recommends.
The 2001 now has 101,000 miles. My 2004 (also 3.8L) has 105,000 miles and I drive it 500 miles a week. Recently replaced an oxygen sensor on the 2004.
Overall, both cars have performed very well, excepting the no-start and stalling problem, which wouldn't have been a big issue if the cause was known and fixed immediately.