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‘99 F250 7.3l 6 speed. I bought this truck new. I would like some comments on normal sounds when Key On. Haven’t pulled any codes or checked for what would be the lack of sounds when key is turned on before cranking engine. Engine starts normally.

Things I’ve done:
1. I purchased a tuner from DP. Tried a couple tunes and wasn’t impressed, Put it back to stock calibration. Loaned tuner never was returned and lost track of borrower.
2. Replaced a vacuum pump. (electric)
That’s about it except for normal maintenance. ( oil changes, filters, etc)

I used to hear several ‘normal’ noises with Key On. Something running for approximately 10 secs.. I always thought it was either a pump (either fuel or vac) then when ‘wait to start’ goes out I would have a normal crank and startup.

Now I don’t hear anything with Key On except that annoying chime if I haven’t closed the door. Tell me what you hear from your truck before cranking.

I know these are kinda dumb questions but I can take a little razzing.
 

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Key on noise starts with fuel pump, vacuum pump, glow plug makes no noise and light is not related to glow plug being powered, light is brain dead timer operated. You should also have the thump from the heater/air control door. SOOOOO it may just be you are old and hearing is going bad, get next to building and you should hear the fuel pump, pop the hood have someone else turn the key and see if you hear the vacuum pump, go under the truck and repeat test for fuel pump. If truck runs it is most likely not fuel pump. If brakes don't work I would look at vacuum pump. Kevin will correct if this is bad advice.
DENNY
 

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Unless the vacuum bleeds off, the vacuum pump won't start.
I rarely hear the fuel pump, unless I really listen for it. Maybe I'm just really old like Denny suggests. ;)
Vacuum has no effect on brakes on our trucks, but maybe Denny meant hub locks if you've got the 4x4 switch on the dash.
 

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Unless the vacuum bleeds off, the vacuum pump won't start.
I rarely hear the fuel pump, unless I really listen for it. Maybe I'm just really old like Denny suggests. ;)
Vacuum has no effect on brakes on our trucks, but maybe Denny meant hub locks if you've got the 4x4 switch on the dash.
I stopped counting so I really lost track of my age , and since I retired I can’t figure out what day it is anyway. Naw my hearing is good, (that’s my opinion)
I have manual hubs, I’ll get somebody to listen with me to determine if the fuel pump is coming up to pressure. I don’t ever recall hearing a thump for the heater door but then again I just got the truck.............. twenty years ago. Maybe I should ask my wife, I am always saying “What’s that noise? Can you hear that?” Lol.
 

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Keven is right I just had a brain fart.
denny
 

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My 99 only has a vac hum when the key on before wts light goes off never fuel pump the only other sound is the relay click on\off for the glows
My 95 on yhe other hand has many clicks and ticks lol
 
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