1994 F-150 Hard starting when engine is warm

[maxxpower]

Hello, I have a 94 F-150 with the 300-6. The truck has 175,000 miles but still runs great. I have been having a problem starting it when the engine is warmed up. It starts fine cold, but if I get it up to temp and shut it off for a while, like when I go to a store for 10-15 minutes, it doesn't want to start up right away. Sometimes it will run like its missing for a few seconds and then die. It takes an average of three times to get it started when its warm. Once its running it runs great with plenty of power. I have recently changed the plugs and fuel filter. Thank you in advance for any replies.

 

[Skinnywater]

Re: 1994 F-150 Hard starting when engine is warm

I'm assuming it has fuel injection.<br /><br />The system needs residual fuel pressure for hot starts. A simple pressure test shows a system that looses all pressure during a hot soak can be caused by injectors that leak down, or a check valve that isn't holding pressure, a leak on the pressure side, or a leaking pressure regulator.<br /><br />The most common at our shop, is injectors that leak down during the hot soak.

 

[DJ]

Re: 1994 F-150 Hard starting when engine is warm

I agree with Skinnywater.