truck repair questions


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Old 03-04-06, 09:21 PM
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Question truck repair questions

I have an 1986 f250 pickup with a 302 v8 with fuel ejection! that has a major problem when it is going down the road it hesitates and hopps! could this be a fuel related? Or could it be lack of air to the engine? any help would be greatly appriaciate the help! tom
 
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Old 03-04-06, 09:52 PM
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tomj,
describe going down the road , highway speeds or what?
auto or straight drive? what does it has as options?
and exactly what do you mean "hoppes"?
we are here to try and help, let us know a
little more about the problem.

barry
 
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Old 03-07-06, 11:36 AM
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could b e fuel spark or computer control related a littel more info may help is the check engine or service engine lamp on ? what speeds and temp dose this happen
 
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Old 03-08-06, 04:37 PM
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1986 f250 pickup!

1986 f 250 pickup with 302 v8 5.0 liter engine with auto transmissionpower stearing power brakes and fuel injection. it does not have air conditioning or any other options! it hesitates like it is running out of fuel travel speed was at 15 to 20 mph going uphill and or straight down the street in town. travel speed of 20 mph was with the gas pedal to the floor. the check engine light is not on and it has a light instead of a gauge! and it was not on! tahnks tom!
 
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Old 03-08-06, 05:39 PM
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'86 250 ford

tom,

when was the last time the fuel filter and the injecters changed and or cleaned
what part of the country do you live?
air filter changed recently?
vacuum hoses to the throttle control fitted up right?
battery good?
sorry for all of the questions again, but it helps us figure out what may be wrong with the truck, and there ain't no way that we want a guy to be without his truck. also i seem to remember that the auto tranny may have something to do with poor performance, anything been done to the transmission?
let us know, we are here to help.

barry
 
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Old 03-08-06, 06:08 PM
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truck repair!

we just inherited the truck from family member we live in east wenatchee wa. do not know what has or has not been done! so i do not have any idea of when these parts where changed! the battery is new! i don't know where to look for the fuel filters? throtle hose? i have tune up parts for it! i am a retired mechanic and i only have worked on the cars from 1980 and back to model t's! these newer cars i haven't a clue! thanks tom
 
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Old 03-08-06, 08:17 PM
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Ford Truck Repair

Having been down a very similar road, I would take a close look at the fuel system. The fuel filter is an inline model. It will be under the vehicle along the frame. If it hasn't been changed, it ought to be. Twenty years is a long time, especially if the truck has set idle for long periods.

The next thing I would check is the fuel pump. It can be checked for proper pressure at an access fitting under the hood if you have the guage. If not, taking it to a mechanic who has the test equipment is well worth the money. Your only other option is to replace the fuel pump. Fuel injected systems require very high pressures to vaporize the fuel as it is injected into the engine. To get these higher pressures, the pumps are located inside the fuel tank. Fords, like most other cars and trucks, have the fuel pumps mounted in the top of the fuel tank with the pump motor, screen and fuelgage float arm all suspended down into the fuel. You will have to either drop the tank to get at it, or do what I did with my Bronco.

I cut an 8 inch square hole in the bed of the Bronco above where the fuel pump is mounted. Doing it that way made it a 45 minute job. Dropping the tank on older vehicles is a real pain. The bolts are usually rusted beyond salvaging and there isn't much room to work with tools between the tank and the frame. Any added tow packages etc. just make it worse. I made a 10" by 10" aluminum cover to place over the hole in the bed, secured it with sheet metal screws, and laid the floor mat back over it. I never had to replace another fuel pump, but it was nice knowing I could do it next time in a matter of minutes.

My son got another 50K miles out of the Bronco without another stuttering problem and sold it to a fireman who is still driving it.

Good luck,

Jim
 
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Old 03-09-06, 04:54 AM
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could be several things but checking fuel pressure would be a good start you may want to see a shop to have it diagnosed as you can easily spend alot buying the equipment needed to do the tests. changing the fuel filter would be a good starting point that you could probably do yourself just loosen the gas cap or caps first and remeber it may be under some pressure when you remove the filter the fuel pressure runs at about 40 psi so it is a good idea to use a rag wrapped around the line when removing to keep the gas from spraying all over for that second that there is actually some pressure bleeding off. it could possibly have more than one fuel filter as these early model fuel injected fords often had both a paper filter in a plastic screw off style canister and an inline filter both on the inside of the drivers side frame rail.
ford used a high pressure pump mounted on the frame you will probably see it when changing the filter and they also used a low pressure pump inside the tank so if you have dual gas tanks it should be equiped with 3 fuel pumps if single tank just 2 pumps while you would need a guage to diagnose the high pressure pump you can check the low pressure pumps by just cycling the key on and off a few times and watching for flow with the fuel line disconnected and running into a container, they are very low pressure at about 5 psi and if you have any flow at all the pump in the tank is usually considered ok you would need to use the switch to check both pumps if it is a dual tank model.
ford used this style up through 1989 then they did away with the on the frame pump and just used high pressure pump in the tank wich was alot simpler to diagnose fuel pressure related problems.
 
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Old 03-30-06, 05:34 PM
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ford truck with fuel problems!

I replaced the fuel filter on the truck it ran fine for one day then started doing the same thing! help what else could it be? I am at a lose! help thanks in advance ! tom!
 
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Old 03-30-06, 05:46 PM
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it probably has a bad fuel pump a fuel pressure test will need to be done to see if its losing fuel pressure and then replace whichever pump is bad.
 
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Old 09-26-06, 10:06 PM
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truck repair f 250 pickup 1986

I am still having problems with the truck we have replaced the fuel filter,tuneup, timed it set fuel injection. as long as the engine is cold it is fine but once the engine is hot it is still dieing out and won't have any power! i have been told it might be the coil or the control modual! could some one please help me diagnose the problem? thanks in advance tom johnson!
 
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Old 09-28-06, 08:40 AM
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Tom:

Along side of the fuel possibilities already discussed, a coil can act up when it gets hot. It would likely show an intermitten missing for a while, then die altogether. Those can be checked for resistance with an ohm meter. Also any connections to the coil can cause a problem. Those are things you can easily look at and clean if necessary.

An ignition module failing fits the cold (good) and hot (acting up). When hot they can cause poor performance and very hard starting. Those can be pulled and checked at a parts store prior to replacing.

Another is the oxygen sensor. An ox sensor won't send signals to the ECU until it reaches 600 degrees. So you would have the cold/hot thing working.

I believe a good place to start would be to pull the codes on the computer to see if that reveals anything. I believe some auto parts stores will do that for nothing.


Hope this helps,

Bob
 
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Old 01-06-14, 10:01 PM
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could b e fuel flash or PC control identified a littel more data may help is the check motor or administration motor light on ? what velocities and temp dosage this happen....
 
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Old 01-06-14, 10:07 PM
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