1995 f150 start up issues
03-13-2019, 11:46 PM
#1
Parts installer
Thread Starter
1995 f150 start up issues
I have a 1995 F150 with the 5.0 L manual trans. Motor is stock other than cold air intake and throttle body spacer. I have seemingly random start up issues. She will crank but won’t fire sometimes. If she sits for long periods 4 or more hours she always fires. If I drive around then park and come back to her she will crank all day, will not fire. Originally thought it was a fuel issue because I would bleed fuel rail and get her to start. That trick doesn’t seem to be working so now I’m thinking it’s a spark issue. I have replaced the fuel pressure regulator but that didn’t do anything. Any help would be very nice, this is getting annoying!
03-14-2019, 05:53 AM
#2
Senior Member
Check for stored codes.
Hang a fuel pressure gauge to determine fuel pressure.
Check for spark.
More fuel pressure regulators get replaced as a guess when in fact they prevent the pressure from going too high.I would pull its vacuum line and look for the presence of raw fuel.
Hang a fuel pressure gauge to determine fuel pressure.
Check for spark.
More fuel pressure regulators get replaced as a guess when in fact they prevent the pressure from going too high.I would pull its vacuum line and look for the presence of raw fuel.
03-14-2019, 09:51 AM
#3
Senior Member
When it does not fire up - i.e. when it cranks all day but not start - check for spark at the coil. If it has spark, I'd bet it is something like the engine coolant temp sensor. If it does not have spark, my bet would be PIP sensor in the distributor or the ignition control module.
But yes, pull codes and measure fuel pressure at the rail on both tanks - this is the first step. Most places don't accept returns on electrical parts so throwing money at it can get expensive.
But yes, pull codes and measure fuel pressure at the rail on both tanks - this is the first step. Most places don't accept returns on electrical parts so throwing money at it can get expensive.
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BigBlue1124 (03-24-2019)
03-14-2019, 11:05 PM
#5
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CAI has been stock on virtually every passenger vehicle since 1975. What did you put on it?Dead weight.
Get a Haynes manual & a digital multimeter (DMM), and start testing every sensor. Click these & read the captions.
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(phone app link)Both are blind guesses, and if dumping flammable liquid onto a warm engine ever helped, it's blind luck you're not dead and just a coincidence that the engine ran afterward. Stop guessing & start diagnosing.
(phone app link)
(phone app link)
(phone app link)
(phone app link)
(phone app link)
(phone app link)
(phone app link)Both are blind guesses, and if dumping flammable liquid onto a warm engine ever helped, it's blind luck you're not dead and just a coincidence that the engine ran afterward. Stop guessing & start diagnosing.
03-24-2019, 11:19 PM
#6
Parts installer
Thread Starter
Thank you guys for the help! I have ruled out everything except the PIP sensor and Control module but also need more help with fuel system. Can you please direct me towards a thread regarding fuel pressure testing and acceptable pressures? Thanks again,
NIck
NIck
03-25-2019, 10:41 AM
#7
Senior Member
The fuel pressure regulator is there to lower pressure when its not needed, so if you pull the vacuum line off of it while the truck is running you should be operating at close to the maximum the pump can put out. This is a good way to diagnose the overall health of your fuel pumps and the flow of the system (i.e. if you have a kink in a line, a blockage, or a bad filter).
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BigBlue1124 (03-27-2019)