Saturn SL1 won't suddenly won't start

This is a 2001 Saturn SL1 Coupe 1.9L 4 cyl automatic with 100,900 miles.
This vehicle has been serviced regularly. I am not sure if a tune up was
done recently. The problem is the car will start fine for a while and
then not start again. The engine begins to turn over but then stops. We
have had the car checked out by our mechanic who says there are old codes
in the system but nothing that would cause it to not start. He is
believing it is a sensor on the motor that tells the computer when to
allow the vehicle to start. Is this possible or could there be another
problem? If you leave the vehicle sit for several hours or more it will
start again but then you don't know when it will not start. The last time
we had the vehicle towed into our mechanic it sat overnight and the next
day it started. Then it quit again and he checked for codes but none were
displayed. Also the service engine soon light stays on as does the service
light with the little wrench. Anyone have any ideas this car is again
sitting in my driveway deciding not to start again. Thanks for all the
help.

You need to better describe the symptoms. Sounds like it turns over at
first, then it stops turning over completely. Is this correct? What other
symptoms occur? How long does it turn before stopping?

Have cleaned your battery connections and cable connectors? Is the cable
end on the starter also clean and tight? Are the ground cables all good ,
clean, and making excellent contact? If the starter stops turning, then
something is stopping it. Look at the circuit, and if not the above, then
it could be the starter relay, the ignition key, or anything in between. If
the starter is turning, then it is not likely the starter or the solenoid,
but, hey, they are also still in the circuit and could be problems too.
Once it locks out you need to do some basic troubleshooting and analysis by
following the circuit.

Bob

"deehk" > wrote in message
lkaboutautos.com...
> This is a 2001 Saturn SL1 Coupe 1.9L 4 cyl automatic with 100,900 miles.
> This vehicle has been serviced regularly. I am not sure if a tune up was
> done recently. The problem is the car will start fine for a while and
> then not start again. The engine begins to turn over but then stops. We
> have had the car checked out by our mechanic who says there are old codes
> in the system but nothing that would cause it to not start. He is
> believing it is a sensor on the motor that tells the computer when to
> allow the vehicle to start. Is this possible or could there be another
> problem? If you leave the vehicle sit for several hours or more it will
> start again but then you don't know when it will not start. The last time
> we had the vehicle towed into our mechanic it sat overnight and the next
> day it started. Then it quit again and he checked for codes but none were
> displayed. Also the service engine soon light stays on as does the
service
> light with the little wrench. Anyone have any ideas this car is again
> sitting in my driveway deciding not to start again. Thanks for all the
> help.

The car never stops turning over but actually starts. If you take the key
out and leave the vehicle sit for part of a day it will start again. It
is almost as if the engine or starter is getting too hot. Does that help?
I am puzzled as is my mechanic.

Okay besides having the problems mentioned in the previous posts I have now
noticed the oil is being used up very quickly. I had an oil change the
middle of August and over the weekend noticed the oil was nearly off the
dip stick. I added a quart and a half and that brought the oil back up to
just below full. I don't see any oil spots in my driveway or any where
else I have parked. Help! Pat.