Cranks but wont start after sitting more then a day

[whtailhunter319]

I have a 96 Ranger 4.0 Auto, 4wd. When it sits for more then a day it will not start. It cranks good but in order to get it to start I have to shoot it with ether. But once its running you can shut it off and restart no problem until it sits for a day or two without running. Its got new plugs and wires, new fuel filter, and ive tested fuel pressure and its within limits. Ive heard of low battery voltage causing this and ive boosted the battery with no improvement. Anyone have some ideas or at least a starting point??

 

[Earl43P]

Will it start reliably if you:

Turn the key to Run (hear Fuel Pump "prime"), turn key to OFF.

Repeat 3X, then crank it over.

If so, Fuel Pressure is bleeding down. It could be:

Seeping fuel line connection (Fuel Filter is a common spot)
stuck open injector
bad check valve in fuel pump

 

[whtailhunter319]

thanks for the input. Ill let it sit over the long weekend and hopefully be able to recheck on Tues. Ill repost my results. Should I find a consistant start how would i check if its a stuck FI or check valve in pump after I elimate any obvious signs?? Having to change the fuel pump wouldnt be that bad as i want to replace the rear sway bushings anyways and if I got 170k out of the pump i can live with that. Just relized I posted in the wrong engine forum... "sigh" its always something...

 

[gw33gp]

If you can check fuel pressure, continue to check it after you shut off the engine. If it bleeds off, it is most likely the check valve in the fuel pump.

Recently, I had to replace my fuel pump because of a bad check valve and it only had 98K miles on it. Now it starts right up after sitting for a while. I confirmed it was the fuel pump check valve by disconnecting the fuel filter and putting a fuel pressure gage on the fuel filter. I built up pressure and watched to see if the pressure bled off and it did.

 

[Earl43P]

You can live with it bleeding down for an AWFUL long time if you simply prime it before you crank it. I would think if an injector was stuck open, you'd feel that with it running, but perhaps not if it is just a seep.

Consensus is that removing the bed is the easier method. I found nothing easy about removing those 6 T-55 bolts, but it came off (42" breaker bar). I did notice it was a 4.0, but it doesn't matter for this problem. Figured you had enough problems without me nitpicking. We try not to run off our new members.

So, while you are doing sway bushings and FP, you might as well replace the shocks and check those rear shoes. Pressure wash the whole thing while you're at it and paint the frame. It never ends, does it?

 

[eso123]

Same situation with cold starting

It seems that I am in the same situation with hard cold starting ('98 XLT 4.0 manual, 169k miles). The priming procedure (KOEO 3x) before cranking/starting seems to be working.

 

[kimcrwbr1]

Check the oil for fuel sniff the dipstick that would be the injector/s. Check the vacuum line for the fuel pressure regulator for fuel, shoud be none. +1 on leaving the fuel pressure guage on after you turn the engine off and watch it. let us know what you find out and what are the pressures with and without vacuum to the regulator at an idle and the pressures when you floor it if it drops could be a weak fuel pump. Try putting about 4 ozs of acetone in the tank when you fill it maybe it will dissolve the crud that may be in the fuel system.