i have a 92 f150 and it makes this weird humming noise, it gets louder as u drive faster, im not sure were it is coming from but it sounds like under the chassis somewhere around the back of the cab, can anybody help me with this, the u joints have been replaced so its not those.

One more ? My same pickup, when i start it the first time, it starts good, but after i drive it a litle and then turn it off for a while and then restart it starts hard, takes a litle longer for it to fire up, any ideas what might be happining, other then i havent changed the spark plugs yet the rotor and cap have been replaced, if anyone has any ideas please post them.

 

Dunno what the humming might be, but got a pretty good idea on the hard start.

Have you replaced the starter? I also have a '92, and the starter started getting slow from a LOT of years of great service. The brushes wear out, some turns in the armature short out, and carbon builds up in the bearings. It may not be dead, but it's certainly old enough to start getting feeble. If it's hot, the conditions will be worsened.

Plan B, the battery could be getting weak. It happens, trust me, twice in the past year on two different Fords.

Plan C. On the '02, the cable splits at the battery terminal. One lead goes to the starter relay, the other directly to the starter. Mine failed in the lead going to the starter, for a NO START condition. Relay picked up, solenoid went CLACK! Just no spinning from the starter. This was fun to find. Cable failed with ABSOLUTELY no evidence of heating or corrosion. Cut the original terminal clamp off, replaced it with a $2.00 clamp, and bingo, problem solve. (But only after replacing both starter and battery. DUHHHHHH)

If the starter's dragging, it'll pull down battery voltage pretty severly, thus affecting spark and a lotta other things. This will probably also accelerate the faillure of the cable in the battery post clamp. Yank the starter, and get it checked. It really isn't that expensive (around $70 for a reman), so for assurance, if you're gonna pull it, replace it. Be ready for some knuckle busting fun if the OE bolts have never been out. Get replacement bolts (Grade 8) if you pull the starter at all. The OE bolts are pretty soft, and chances are, you're gonna wreck the head on one of them. (Then the real fun begins) The grade 8's will probably wreck your socket before you hurt the bolt. The replacment will come with a short wire attached on the post for the solenoid coil. You're gonna have to cut the original slide-on connector off and splice the wire. No biggie, and better connection. The slide-on tends to self destruct anyway, again, causing a NO START condition.

 

had a similar problem on my 92 F150 and the humming noise is the rear in-tank fuel pumps; they will need to be replaced. my F150 has the dual option tanks so both had to be replaced at the same time. your symptoms are similar to mine in that the humming is in the back of the cab and when you turn the truck off and try to start again it is hard to start-up. i replaced two starters and a regulator that i thought were bad but in the end it was the in-tank fuel pumps. when i had mine done 5 years ago it cost $150.00.

 

OOPs, I said '02 in Plan C. I meant '92.

When you say "starts hard" does that mean it sounds like it's turning over more slowly, or that it just takes longer to crank? I may have misinterpreted your meaning.

Yes, low fuel pressure would certainly cause it to have to crank a little longer, but you'd also notice this with poor idling and really lousy performance on the highway.

 

i think redo92 hit it right on the money, thanks guys

 

I've had F150 pumps that have been whining for years. But They didn't give me any problems (not start). I have worked at ford garage and never heard or "having"to replace both at 1 time. Sound more like regualtor to me . And out of 15 F series and about 600000+ plus miles only replaced 1 . And that was on NEw 94 F150 at ford garage 8 months ago(warrenty) Just because of warenty. They only replace front(noise) pump. Keep us posted.

 

well my is gettin close to 200,000 miles on it, motor runs real good for the miles, some time here i am going to get true straight pipes, i think and engine should true, not muffled, anyways ill keep u guys posted