Question1.5L 12 V engine,126,000 mi.[hiway miles,I commute 86 mi. per day]Regularly serviced.Engine quits running when warm.No check engine light or any other light[all lights do work].Let it cool approx 10 min,will crank again.Fuel filter new,is in time. Any ideas?
AnswerI'd primarily suspect the fuel pump or a crank sensor.
If you have no spark when the problem occurs, look for a crank sensor issue. Possibly even check to see if you have any trouble codes in the ECM.
You'll need to install a fuel pressure gauge to check the fuel pump. The specification in the shop manual is 50 PSI, but I think this is high, even with the vacuum hose disconnected from the regulator. If I recall correctly, the pressure should be about 30 or 35 PSI with the vacuum hose connected, and about 5 more PSI with the hose disconnected. If that's okay, momentarily pinch the return hose shut with a pair of needlenose pliers. The pressure should go up to 80 or 90 PSI. If either reading is low, replace the fuel pump.
Due to the length of your trip, it's possible that you have a fuel pump issue and it'll test okay while the vehicle is cold. You may need to test the fuel pressure while the problem is occurring to get a good answer.
