Whining

[Neal Cox]

I have a 2003 Sport Trac 6 cyl XLS, not the flex fuel. Recently I've had two problems, I can't quite figure out.

1st, is a whine under the truck. High pitch. I hear it when the truck is in drive and i'm at a stop. If it happens when i'm driving, i'm not sure. I hear it when i'm at a stop light or at a drive through. If i put the truck in neutral the Whine goes away. It's very loud under the truck, but i can't quite find it.



2nd, The truck with a full tank of gas, at least the gauge said full, stalled while at an idle at a stop light, wouldn't start, acted like it was out of gas. On a whim, i pushed the emergency gas shut off switch under the dash on the passenger side, and it started. It's running okay now, but i'm worried it will happen again.

Does anyone have ideas? The economy isn't going to let me take this one to a mechanic to let them play with.

thx.

 

[David Ponder]

Hi Neil,



First off, :welcome: to the site. Always glad to have new members here. There is a wealth of information available here, and you will find that many of us will go out of our way to assist another member when we can.



Your first issue I believe is simple. The Fuel cutoff switch (aka Inertia switch) is bad. There have been several that have had this same problem. Dont trust one from a slavage yard, just order a new one, install it, and be done.



The second issue is more complex.. If you hear the sound at a complete stop, that rules out rear end whine, U joints, Front Diff, wheel bearings, etc... // Do you believe the whine to be more mechanical sounding, or more of a high pitched whistle? Does it only do this in drive, or also when in Park? A vacuum leak may cause a high pitch whistle sound. If mechanical, it may be something in the transmission. I would take it to a reputable transmission shop and have them put it on the rack and they can have someone under the vehicle take a listen. Many local shops will "Have a listen" for a little or nothing diagnostic fee. If the problem is in the transmission, then fixing early before it gets worse is key here.



Good luck, and please keep us posted. Knowledge is our best friend!



Dave

 

[Richard L]

nealmed,

I think Dave is correct about the fuel pump cutoff switch. If this is the first time it has cutoff, don't panic, if may have just been a fluke. It may never happen again, but it might happen again tomorrow. If it does happen again in the very near future, then I would go ahead and get a new switch. As Dave said, get a new one (does not have to be from Ford), but that's the kind of part that should NOT be aquired cheap from a junk yard.



As for the whining noise....Have you lifted the hood and listened while the engine was idling?

It may be something as simple as a bad belt, or belt tensioner (known to be a weak link) It may also be the Alternator bearings.



If it sounds more like a whistle than a whine, it might be a vacuum leak or be caused by the air cleaner. Many people who have switched to different types of air cleaners have reported some whistling sounds.



Finally, if the noise is not coming from under the hood, but is coming from under the vehicle, it sounds like it might be a tranny issue. Before you run out and let some transmission shop tell you that you need a rebuilt transmission, get the fluid flushed and see if that does not make a difference.



...Rich

 

[scott degroot]

HMMM...A high puitched whine from under the vehicle and truck stalling acting like it's out of fuel...can anyone say bad fuel pump. On alot of GM trucks fuel pump whine is almost normal but on Fords fuel pump whine is something to be concerned about...I'm betting that your pushing of the fuel cutoff was nothing more than a coincidence and your fuel pump is about ready to go out.

 

[Richard L]

l1tech,

Good point...Since both issues were stated as being separate issues, I never thought to link them. Yes, the whining from under the vehicle could be the fuel pump, even though I never heard a fuel pump whine...:grin:



I would still look under the hood and listen for things like whining alternators, or bad belts and belt tensioners before I dropped the fuel tank.



Of course sounds are very hard to diagnose without hearing them yourself. What sounds like a whine to one person may be a groan, buzz or a humm to someone else..:banghead:



....Rich

 

[Kevin Palmer]

I am also betting the whine is the fuel pump.



It could be putting enough drag (electrically speaking) causing the inertia switch to trip/pop...

 

[scott degroot]

^^^^



A high load on the inertia switch will not casue it to trip. Basically the inertia switch is just a steel ball held in place by a magnet. When a force great enough to dislodge the ball from the magnet is introduced the ball falls and breaks the flow of electricity through the switch.

 

[David Ponder]

Duh... :banghead:



L1, you are probably right, I also didnt put the two together... Neal, if it makes the noise while running in park, have a listen under the truck at the fuel tank.