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Hard starting when engine is warm.

  #1  
Old 07-02-2009, 12:30 AM
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Default Hard starting when engine is warm.

My 1999 24V (125k miles) is difficult to start when the engine is hot. When I first get in the truck in the mornings it fires right up, but after driving a bit if I turn it off and then try to start it, it just turns over fine but no starting. After cranking 10~20 seconds it does start. If I let the truck sit 4 hours or longer after driving it always starts right up. There are no codes. My VP44 is a little over a year old, as well as Edge Jammer injector tips. As for the lift pump replacement I'm running the FASS system. I'm showing plenty of fuel pressure (idle 15+ psi) before the VP44. Anyone have a idea as to what is causing my problem?

Thanks.
 
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Old 07-03-2009, 01:24 AM
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Have your batteries and starter tested.
If you don't have good cranking rpm you get hard or no starts.
 
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Old 07-05-2009, 09:57 PM
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Batteries were just replaced less than 4 months ago and the starter is about 2-3 years old.
 
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Old 08-14-2009, 03:08 PM
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Default Fuel Pump

The fuel pump might be going bad. It might have a leaky check valve.
 
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Old 08-16-2009, 05:35 PM
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My '01 is doing the same thing. I have noticed where the lines are going to the injectors some are leaking (leaking from inside or behind where it screws in) . I am thinking seals inside the injectors (IF there is any) after warming up they swell and allow fuel to leak?
Does this sound plausible?
Thats what I'm thinking. If it was the injectors themselves, it would do it all the time I think?
Its really pissing me off though.
FYI, I have replaced my IP and lift pump assembly less than a yr ago.
 
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Old 08-17-2009, 07:41 AM
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That sounds to me like you're getting some air in the lines.

Check all your fuel lines and make sure you don't have any cracks or leaks anywhere.

When the VP44 loses prime, it's a PITA to re-start.

Other things I'd look at is a clogged fuel filter / water seperator.
 
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Old 08-19-2009, 08:33 PM
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It DOES appear that leaking or broken fuel lines would be the obvious culprit but why only when its warm? Why not all the time?

In MY situation I DO see a little bit of fuel and its leaking from where the fuel lines go into the injectors (and they are TIGHT). Not pouring out but seems to be leaking. I don't see any leaks anywhere else from the tank all the way up to the filter, into the IP, etc.

thanks
 
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Old 08-21-2009, 12:25 AM
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It's possible for a leak between the lift pump and tank to suck in air and not have a fuel drip. Splice in a section of clear hose and look for bubbles or foam. bubbles = air leak
 
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Old 08-21-2009, 12:47 AM
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injection pump is going bad
dam you VP 44
 
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Old 08-21-2009, 07:36 AM
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Originally Posted by hounds
It DOES appear that leaking or broken fuel lines would be the obvious culprit but why only when its warm? Why not all the time?

In MY situation I DO see a little bit of fuel and its leaking from where the fuel lines go into the injectors (and they are TIGHT). Not pouring out but seems to be leaking. I don't see any leaks anywhere else from the tank all the way up to the filter, into the IP, etc.

thanks
Hounds,

That sounds to me like the fuel line nut got overtightened and the compression fitting is shot.

The fitting between the HP fuel line and the connector tube is a compression fitting and, really, it's only suppossed to be used once. Can you get away with removing an installing it multiple times? Yes, but you need to ber very careful not to damage the head of the fuel line, otherwise a leak develops.

This can either leak fuel under pressure or it can allow air in when the system is off.
 

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