300/6 - Ford F150 Forum - Community of Ford Truck Fans

Topic Sponsor
1987 - 1996 F150 Still running strong! Talk about your 8th and 9th generation Ford F150 trucks.

300/6

 
Old 02-05-2019, 05:55 AM
  #1  
Junior Member
Thread Starter
 
Join Date: Feb 2019
Posts: 3
Thanks: 0
Thanked 0 Times in 0 Posts
Default 300/6

Hi my 1989 f150 300/6 has a hard starting problem when warm when i turn it off for a while then go back to start it and crank a long time till it finally fires or give up and cycle the key start again and it firs right up, ive done the fuel filter and ignition kit ie cap rotor leads and plugs, its had a new in tank pump in front tank but doesnt seem to make any difference which tank its running on?
I am thinking main fuel pressure or regulator but havnt got that far yet.
Also how much can you lower the front springs before it upsets the geometry? Ive got longer swing shackles for the back and want to lower the front to suit as its on 18s and sits a bit high.
many thanks Baz

cusso55-56 is offline  
Old 02-05-2019, 06:10 AM
  #2  
Senior Member
 
Join Date: Oct 2016
Location: Ohio
Posts: 394
Thanks: 0
Thanked 50 Times in 43 Posts
Default

Check your fuel pressure. Your spec is 45-60 psi at idle.Pull the vacuum line off the regulator, pressure should go up and there should not be any raw fuel at the vacuum port of the regulator, otherwise it is bad . Make sure it holds pressure after shut down.

Last edited by raski; 02-05-2019 at 06:13 AM.
raski is offline  
Old 02-05-2019, 03:50 PM
  #3  
Junior Member
Thread Starter
 
Join Date: Feb 2019
Posts: 3
Thanks: 0
Thanked 0 Times in 0 Posts
Default

Thanks found a mate has a EFI test kit last night so hoping it got a fitting ti fit the scrader valve on my truck soon.
cusso55-56 is offline  
Old 02-07-2019, 10:17 PM
  #4  
Member
 
Shagg's Avatar
 
Join Date: Oct 2017
Location: Central, VA
Posts: 66
Thanks: 0
Thanked 2 Times in 2 Posts
Default

I had a similar problem with my truck. If it had sat for a day or two, it would fire right up, but if the engine was warm, then it would crank for a while. it turned out to be a fuel pressure regulator for me, which was just a $10 fix.
Shagg is offline  
 


Thread Tools
Search this Thread
Quick Reply: 300/6


Contact Us Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: