How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask George H. Your Own Question
George H.
George H., Hyundai Technician
Category: Hyundai
Satisfied Customers: 18393
Experience:  Hyundai Gold certified, ASE Master tech 15+ years
13574682
Type Your Hyundai Question Here...
George H. is online now
A new question is answered every 9 seconds

Fuel pump doesnt seem to energize when I turn the key on.

Customer Question

Fuel pump doesnt seem to energize when I turn the key on. Car wont start
JA: Is the car in "Park" or "Neutral?" Do you know if your car has a "wheel lock" feature?
Customer: Car is in Park. 2004 Hyundai Sonata 2.7
JA: Are you hoping to fix this yourself? What have you tried so far?
Customer: Had a new fuel pump and filter installed 2,000 miles ago. I'm thinking relay or crankshaft position sensor
JA: Anything else you think the mechanic should know?
Customer: Pending ECM codes forP1507 and P1505
Submitted: 4 months ago.
Category: Hyundai
Expert:  George H. replied 4 months ago.

Hello I will help,

The fuel pump is turned on when the computer sees the engine turing 250 rpm or more. Simply turning on the key does not run the pump.

The codes indicate a problem with the idle speed control but that would not keep the pump from running.

It is common for the crank sensor wiring's insulation to fail, if it is cracked replace the sensor. It is just above the starter.

Does your code reader show data? RPM while cranking?

Customer: replied 4 months ago.
I can get that info. I used to hear the fuel pump every other time I turned the key on until it reached pressure
Expert:  George H. replied 4 months ago.

The pump only runs when the computer sees 250 rpm.

If you can see a RPM reading then the crank sensor is OK. If the reading is lower than 250 - 300 like half then the IFS is the problem.

That would be my first stop, you can jumper the fuel pump relay from #30 to #87 pin socket to run the pump, if it has no spark it is not the pump.

Could be they spliced the pump rather than using the connectors and a splice has failed.

Let me know how I can help you test this

Thank you