A new question is answered every 9 seconds

1994 ford ranger: i first crank it up it starts up fine..engine warms

Customer Question

my 1994 ford ranger 4.0 sometimes does not want to start after it warms up i cant seem to figure out why? it's only after it runs in the morning when i first crank it up it starts up fine. so it has to do with something when the engine warms up the engine light is not on by the way
Submitted: 6 years ago.
Category: Ford
Expert:  A. Penland replied 6 years ago.


You should check for fuel pressure when the truck will not start. On the metal fuel rails for the fuel injectors there will be a schrader valve. It looks like a tire valve stem. Press the needle valve down in the schrader valve and see if you get a big spray of fuel. You may have a bad fuel pump or fuel pump relay. But check and see if you have fuel pressure when the Ranger will not start when hot. Let me know what you find. Don't replace anything just yet.

Customer: replied 6 years ago.
ok actually i just got threw replacing 3 fuel pumps before i found out that the fuel filter was so bad it was buring up the motors and i can hear it runing when i turn the ignition on, so i hope it isnt that but the fuel pump relay could be bad havent tryed messing with it yet but thanks i will let you know what happens im asuming i just put a regular tire preasure gauge on the schrader value and i will be able to see what the presure is
Expert:  A. Penland replied 6 years ago.


Do not use a tire pressure guage. You will need a fuel pressure guage. A tire pressure guage only measures air pressure. It will not measure fuel pressure and the system needs to be enclosed when testing fuel pressure. You do not want any fuel leaks. Fire hazard may happen.

Below is a fuel pressure guage.


Plus if the fuel pumps were burning up, the relay may be burned up also.

Edited by APenland on 4/8/2010 at 12:29 AM EST
Customer: replied 6 years ago.
ha i just tryed it before i got your reply it was saying around 29 psi but i see what your saying about the fuel presure gauge i really dont think it has anything to do with the fuel i think its more of an air problem you dont think it could be any of the sensors or anything
Expert:  A. Penland replied 6 years ago.

Try a couple of test.

Unplug the IAC and start the truck and see if it stalls. You may have a vacuum leak.

The only way to find out if you have any bad sensors is to get the codes from the engine computer. The connectors to connect to are under the hood. Below are a couple of diagrams to use to get any codes. You will need a jumper wire graphic


No special equipment hookup is required. STI is jumpered to SIG RTN at Self-Test Input (STI) connector and the Data Link Connector (DLC).

Then count the check engine light flashes for any codes and write them down. They will be 2 digit codes.

Customer: replied 6 years ago.
ok i will
Ask A. Penland Your Own Question
A. Penland
A. Penland, Ford Senior Master Technician, ASE
Category: Ford
Satisfied Customers: 6143
Experience:  ASE Master Certified, ASE Advanced Gasoline Engine Performance
Type Your Ford Question Here...
A. Penland is online now
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.

What Customers are Saying:

  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
< Previous | Next >
  • AlvinC answered a question about my Ford truck that only someone with an in-depth knowledge of his subject would have known what was going on. Rich D USA
  • Because of your expertise, you armed me with enough ammunition to win the battle with the dealer. They are installing a fuel filter and fuel pump at no charge to me. Molly USA
  • I needed help with my car on Saturday morning....got a response in 5 minutes, and it was the perfect solution. Thanks again to your service. Jason V. Kirkland, WA
  • I do know, after going though this with JustAnswer, that I can somewhat trust my mechanic but I will always contact you prior to going there. BR New Jersey
  • I would (and have) recommend your site to others I was quite satisfied with the quality of the information received, the professional with whom I interacted, and the quick response time. Thanks, and be sure that I'll be back whenever I need a question answered in a hurry. Stephanie P Elm City, NC
  • used your service this weekend with "Trecers" help. thank you ,thank you, thank you. replaced an A/C fan motor. Local Auto Zone had part. $15.00 "tracer" fee and $40.00 for parts, I saved several hundreds of dollers at a shop. i will recommend you and use you in the future. David L. Richmond, TX
  • 9 dollars, 2 hours of my time, and I drove away. Your diagnosis was right on the mark. Thank you so much. Phil Marysville, CA

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

Meet The Experts:

  • Ron


    ASE Certified Technician

    Satisfied Customers:

    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
< Last | Next >
  • http://ww2.justanswer.com/uploads/FO/fordguyu/2015-7-7_172556_onnieew.64x64.jpg Ron's Avatar


    ASE Certified Technician

    Satisfied Customers:

    23 years with Ford specializing in drivability and electrical and AC. Ford certs and ASE Certs
  • http://ww2.justanswer.com/uploads/MU/muddyford/2012-6-13_1204_1.64x64.png Chris (aka- Moose)'s Avatar

    Chris (aka- Moose)


    Satisfied Customers:

    16 years experience
  • http://ww2.justanswer.com/uploads/JM/jmcdo28/2012-2-23_01655_resized.64x64.jpg John Mc's Avatar

    John Mc

    Ford Technician

    Satisfied Customers:

    19 years Ford Lincoln Mercury experience
  • http://ww2.justanswer.com/uploads/wmarti7/2009-4-18_04332_Avatar.jpg Chuck's Avatar


    ASE Certified Technician

    Satisfied Customers:

    33 Years Experience,Ford Senior Master,ASE Master,L1 Advanced Engine Performance
  • http://ww2.justanswer.com/uploads/BL/Bluegorilla/2012-6-21_16298_cam.64x64.JPG Cam's Avatar


    Journeyman Automotive Technician

    Satisfied Customers:

    GM Grand Master Technician 2007. 14 years Automotive experience.
  • http://ww2.justanswer.com/uploads/CR/crzydrvr00/2013-11-3_12123_246347.64x64.jpg Richard's Avatar


    ASE Certified Technician

    Satisfied Customers:

    12 years at a Ford Lincoln/Mercury and Jaguar dealer as a technician and shop foreman.
  • http://ww2.justanswer.com/uploads/BA/baddad1/2014-4-1_23659_avatar.64x64.jpg Mike V.'s Avatar

    Mike V.

    Auto Service Technician

    Satisfied Customers:

    25 years experience on all makes and models, Licensed NYS Inspector.