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 Chris (aka- Moose) Your Own Question
Chris (aka- Moose)
Chris (aka- Moose), Technician
Category: Ford
Satisfied Customers: 47985
Experience:  16 years experience
2499435
Type Your Ford Question Here...
Chris (aka- Moose) is online now
A new question is answered every 9 seconds

My 98 ford f150 4.2L will not start without a delay. The

Customer Question

My 98 ford f150 4.2L will not start without a delay. The delay when it is 80 degrees F and hotter is about 6 seconds and increases as temps. drop. When it's 30 degrees or less, the delay takes up to 20 mins. During the delay (crank won't start) period, I can hear a very faint humming coming from under the truck. When the truck is ready to start, the CE light does a real quick off/on blink and the humming stops. The truck starts and runs perfect whether idling or when I put my foot into it. I can't locate the fuel rail or the pressure relief valve to see if I have fuel pressure during this delay or not due to all of the other engine parts that may be hiding it from view. After reading a hundred or so forums, I still haven't found anyone that has had this delay. Or they don't know about the delay and just describe it as "crank won't start." I checked the FP relay and fuse and they are both good. The truck only has 30K miles on it so it has done a lot of sitting during it's days. I have read fixes to the "crank won't start" problem from a loose wire/ bad wiring harness in the system to bad PCM with a lot of people changing the fuel pump and it not being the solution. It looks like the PCM on my truck will run about $400-$500, which I can't locate on my truck, and replacing the fuel pump via bed removal though cheaper than the PCM, will take a whole day of labor with my skill level. Have you ever heard of this and can you make any suggestions of things to check before I replace the PCM or FP?
JA: Has your car been stalling?
Customer: No
JA: Are you fixing your F150 yourself? What have you tried so far?
Customer: Checked the FP relay and fuse. Both are good.
JA: Anything else you want the mechanic to know before I connect you?
Customer: Not than I can think of.
Submitted: 7 months ago.
Category: Ford
Expert:  Chris (aka- Moose) replied 7 months ago.

Welcome, I'm Chris (aka Moose), my normal schedule online is around lunch and after dinner till early morning.

I too agree checking the fuel pressure is a good place to start. You want to see an immediate spike of 35psi or more when the key is turned on. Below is a diagram of the test port.

https://dl.dropboxusercontent.com/u/90220402/fptest.png

Please read this:

  1. Understand it's not one answer and done. We can communicate back and forth many times.
  2. I do not work at or for Just Answer. You and I can only communicate on this page.
  3. When you're pleased or happy with my answer or efforts to help you. At the top of the screen please rate me or reply and say ( I'm pleased.)
  4. When I help you I am only paid from your question value deposit when you rate me on this screen. Rating does not close the post and you're more than welcome to follow up.

Thanks for using Just Answer, Chris

Customer: replied 7 months ago.
Thanks for that suggestion Chris. I didn't get a chance to do anymore checking on it, before it was scheduled to have the recalled fuel tank straps replaced. So I just had them diagnose it. After their diagnostics tests to eliminate any thing else, or additional problems, they concluded that it was the EOM. The humming I heard coming from underneath my truck until it was ready to start, was the fuel pump in prime mode. The tech said that it was failing to shut off after 2 secs., and that decision... was coming from the EOM. Replaced, installed, and re-programmed for $530. The parts for my fuel tank and the EOM will be in in 3-5 days. I'll let you know what the results are.
Expert:  Chris (aka- Moose) replied 7 months ago.

Thanks for keeping me updated.

Customer: replied 7 months ago.
The Ford dealer's diagnosis was correct. With the truck being a 98 model, Ford didn't have a new EOM for it so they had to use a rebuilt one from a third party. While they were attempting to diagnose it, they found my battery was only producing about 50% of it's cranking power. Needing 100% (or close to it) to have a reliable diagnosis I told them to replace it. With that being said, the new battery, EOM replacement (1-year warranty) and taxes came to $680 for the total bill. Ending my 2-year dilemma of waiting from 6 seconds on a hot day, to 20 minutes with temps. under 30 degrees made it well worth that. I hope the information I have shared will help you point someone in the future, directly to the problem instead of having to replace several parts as a process of elimination and they reward you handsomely for it. Thanks again.
Expert:  Chris (aka- Moose) replied 7 months ago.

Glad you got it resolved, sorry I was not given a chance to help you diagnose this.

Related Ford Questions