Fuel System Problem

1999 MERCURY MYSTIQUE
113,000 MILES • 2.4L • V6 • FWD • AUTOMATIC
Avatar
SULLUM100
  • MEMBER
  • 5 POSTS
Hello, i had my car's fuel pump changed a couple months ago since it would die out on me while i was driving at any random time. two days ago it did the same exact thing i had my air conditioner on drove it for a good hour then out of no where the check engine light came on and started to stall out then died on me. i got it to start then a couple miles it started to stall out and did not start.. I had the starter replaced, the mechanic said they cannot find the problem until they see it happen, but it has not happened since two days ago, but it does not start right up like it used to, help any ideas?
Jun 24, 2016 at 2:14 PM
Advertisement
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.
Avatar
CARADIODOC
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 34,308 POSTS
That is not how failing fuel pumps normally act. The check engine light is proof the fuel pump is not the cause of this problem. They are not monitored by the Engine computer. That computer did detect a problem. It set a diagnostic fault code and turned the check engine light on to tell you. The place to start is by having the codes read and recorded. That will indicate the circuit or system that needs further diagnosis, or the unacceptable operating condition. It is important now that you do not disconnect the battery or let it run dead. Doing so will erase the codes and that valuable information will be lost.

The most common suspects for this symptom are the crankshaft position sensor and / or the camshaft position sensor. Sometimes the engine stalls too quickly for a fault code to set. Then the mechanic has to go by the other symptoms and observations. He will check for loss of spark and fuel pressure, but those tests are only of value when the problem is occurring.
Jun 24, 2016 at 2:58 PM