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-   -   Hard Starting 4.9 question. (https://www.f150forum.com/f86/hard-starting-4-9-question-397540/)

A pause for the COZ 10-21-2017 01:38 AM

Hard Starting 4.9 question.
 
Ok I went and picked up my 94 F250 4.9 2wd AT 108.000 mi
I have a few ticky tack things to fix.
But what I noticed right a way was how hard it was to start. At first...
Turned over for a extended bit of time with no action. Then it started to sputter a bit like 3 or 4 times.
Then she took off.
Once started she purrs like a kitten, fantastic oil pressure. Nice and smooth running.
Turned her off and she started right back up right away zero issues.
Off and on about 7 or 8 times no issue.
I figured well maybe its just because it had sat for a while.
Drove her home 150 miles. Nice smooth uneventful drive.

Well the next morning... Same issue very hard to start but great after the first start.
I am smart enough to know that wont continue. Eventually I am going to be walking home with the truck on the side of the road.
I would like to preempt that scenario.
What direction would those symptoms be sending me?

88xlt 10-21-2017 12:10 PM

It sounds like you are losing fuel pressure when the truck sits for a while. I would get a fuel pressure gauge to confirm this. Then you would need to figure out where you are losing the fuel pressure. Meanwhile I would turn the ignition switch off and on about 10 times, waiting a few seconds in the on position, to build up the fuel pressure before a cold start to see if it starts easier.

A pause for the COZ 10-22-2017 05:08 AM

Thank you. I was kind of thinking the same thing.
I did let it wait after hearing the pump kick on today and it did start quicker.
So might be onto something.
I did notice that the front tank had been removed at some point in its life. All of the fuel lines and electric parts are still there.
Just no tank or filler parts.
No fuel leaking or anything.
But it is worth more investigating.

justintendo 10-24-2017 10:16 PM

does this an aftermarket oil pressure gauge? the stock is just a dummy switch. it will always read great unless oil pressure drops to an absurd amount, like 3 psi.

important on these (especially the 4.9) to actually check pressure. you definitely are describing the symptoms.

raski 10-26-2017 06:13 AM

Leaky injectors, fuel pressure regulator, fuel line leaks and faulty check valve in fuel pump can cause pressure problems and quick bleed down when the engine is shut down.

A pause for the COZ 11-01-2017 11:34 AM

Thanks Guys I appreciate your help. Learning loads about the 4.9 as I go.
I did get a fuel pressure test gauge and KOEO it read 45psi KOER it bounced at 45psi. Spec is 45- 60
But at the time she started right up no issues.
Two days before it would not start at all just spun over.

I did notice while looking at the tank with the engine running.
The fuel pump is making allot of noise. Howling pretty good.
I noticed that I also need to replace a spring hanger. So I am going to pull the tank, Replace the fuel pump and regulator. Then put a new hanger in before putting the tank back up. This is the rear tank. I actually dont have a front tank in this truck. I will actually remedy that after a trip to U Pull our parts some time this winter.

Chris_1 11-02-2017 08:22 PM

On a 94 4.9 the fuel pressure spec is 30 to 45. They lowered the pressure after a lot of warranty recalls for blown check valves. Mid 93.
I would see what the pressure is after sitting overnight first time you turn the key on.

A pause for the COZ 11-13-2017 01:27 PM

Got-R-Done!
I replaced the two hangers and the fuel pump and filter.
Seems to have solved the problem. Nice and smooth even when giving her the groceries going up a hill.

https://cimg2.ibsrv.net/gimg/www.f15...3a32071f46.jpg
https://cimg4.ibsrv.net/gimg/www.f15...98611bd294.jpg
https://cimg4.ibsrv.net/gimg/www.f15...4561b0c12b.jpg
https://cimg5.ibsrv.net/gimg/www.f15...41ebc94b50.jpg
https://cimg4.ibsrv.net/gimg/www.f15...68a2ed1fb7.jpg
https://cimg7.ibsrv.net/gimg/www.f15...e56e8b904d.jpg
https://cimg8.ibsrv.net/gimg/www.f15...1fc86d77a1.jpg

justintendo 11-13-2017 05:36 PM

nice, common issues with these..

A pause for the COZ 11-14-2017 09:11 AM

well that did not solve the hard starting. Back to the drawing board. Fixed some things that needed fixing but still need to hone in on the real problem.
I had not replaced the fuel pressure regulator yet. So I will try that next.
Thing I find of interest, yesterday after changing the pump and the filter. No fuel in the system. It started much easier than today.
It actually has not started yet. i have the charger on it. But it was getting ready to pop.


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