Stumped with problem on my 97 pontiac sunfire

pontiac
sunfire

#1

Recently i have a problem with my car starting after i have driven it for say 10 to 15 mintues. when i turn off the key it will not start again( it does try to turn over but sounds like it is starved for fuel) when it is left to set for a couple hours you can start it again and drive.


#2

When was the fuel filter last replaced?


#3

Try introducing a volatile into the air horn. If it fires with an outside fuel supplied, then your suspicions are correct. It’s a fuel supply problem. Something like the fuel pump relay not re-energizing upon restart.


#4

Failure to restart after extended runs followed by normal starting after cooling are far more typical of ignition problems than fuel supply problems. When you shut the hot engine down, the coolant stops flowing and the air stops flowing by, and the heat internal to the engine (much higher than your underhood temp) dissipates by radiating out the sides and top of the engine, raising the temperatures under the hood and the temperatures of all the peripheral components. Some ignition components such as coils can become sensitive to heat as they age.

Carry a spare spark plug (or a spark tester) with you and the next time this happens see if you have spark. Post the results here.


#5

i will check my records and let you know tomorrow.
Thanks


#6

will try this tomorrow moring and let you Know.
Thanks


#7

I have had a couple of Ford fuel pumps that would do exactly that…run until hot and then quit and start just fine after cooling. I too first suspected the ignition system, but then I started carrying a fuel pressure gauge and found the problem right away.


#8

There are small pencil sized spark test lamps you can clamp onto spark plug wires. Then, have someone crank the engine while you observe the spark test lamp. If there is spark, the test lamp will flash about once every two seconds during cranking.
Some auto parts stores will have the spark test lamp.
You could check to see if the problem is lack of fuel by spraying a starting fluid into the engine intake. If the engine then starts, the problem is lack of fuel. Further tests would then be needed to check fuel pressure, etc.


#9

If you end up with spark one other thing you can try out as part of diagnosing is to floor the gas pedal while you try to start it. If it fires up then you likely have a leaky fuel pressure regulator or leaky injectors flooding the cylinders. (The gas pedal to the floor helps clear the flooding, if present).