Top 20 1991 Ford F150 Questions & Answers

Check your fuel selector valve for proper working condition. The internal valve may be stuck.

Sounds like stuck floats to me. Unless they are actual sensors. In that case they are not reading correctly. And therefore should be replaced. Unfortunately either way I think you are going to have to pull the tanks. Not a fun job at all. If you have an OBDII and I think you do. Go to our local parts store and they can hook up to it and pull fault codes from the ECM (electronic Control Module). You might get lucky and it will tell you what is wrong. If that doesn't work out for you. Consult with Ford, either online or at the dealer. They might be able to steer you in the right direction. Probably try to steer you into one of the repair bays. But you stay strong, resist the service person. You can do this, I believe in you! Well I know I can do it. Therefore I believe you can too! Good luck, Jason

Wire that doesn't test as bright could have frayed wire/short or fuel pump may be bad.

unlikely to have 2 filters as it will have only one line from the operating tank

On this one, You will need to know where the water is leaking from and oil as well. Sounds like a hose or Tstat gasket. The oil leak cud be the gasket on the oil filter. If you need further help, reach me via phone at https://www.6ya.com/expert/gary_9c859f4aa7e5ab10

likely to be a flat battery. try starting using jump leads from another vehicle. possible you have a faulty alternator not keeping battery charged or something is draining battery when engine off

Check dash gauges. Are they stepper motor type. Check internet for repair service if so. Around $125

Look in t he fuse box lid under the hood. It should have a diagram of the location of the relay.

Sounds to me like you have a broken linkage from your ignition tumbler to your ignition switch. It is a plastic "arm" that pushs.pulls a metal tab on your ignition switch.

Did you change out the fuel filter's?Are fuel injectors clogged.

Are you getting power to the coil? If coil voltage is low, suspect the radio capacitor is shorted. If the voltage is good, the problem may be the ignition module. One other possibility is a problem with the distributor pickup coil or connector. See 2nd page at link below. http://www.revbase.com/BBBMotor/Wd/DownloadPdf?id=15586

Check the bulb. The problem has to be right there at the socket for the left rear. You do understand how the two filament bulbs work? The brake and turns use one filament, while the park lights use the smaller , less bright filament. And the bulb has two buttons on the bottom that touch two buttons in the socket. That is how the current is carried separate for the two lights. It sounds like your bulb is wrong, or the socket itself is compromised.

Did you also change the Coolant Temperature Sensor? If it is reading wrong, the computer may not realize the engine is cold, and won't increase the gas for that. Spray some carb cleaner around the outside of the throttle shaft, if engine speed increases, that could be a vacuum leak. I've never heard of that, but anything is possible. It sounds like it would have to be a serious air or vacuum leak to cause your problem. Have you blocked off the power brake booster to check if that is leaking? You might want to do a compression test to see if there is any internal mechanical damage.

Well furst of all fix the leak before you have a fire.

You might want to check for a busted fuel pressure regulator diaphragm. With the engine running, pull the vacuum line off the regulator. If gas comes out of the regulator, replace it. For the acceleration issue, check the signal on the map sensor. It should change drastically when you open the throttle.

You need to do an EEC IV engine control system fault code test, you can do that without special tools by following the instructions at the link below. EEC IV Self Test Ford Fuel Injection and EEC IV Electronic Engine Control...

Sounds like the connection broke at the throttle at the intake. Take a look to see if the clip broke. don-ohio

You have the key cylinder drive gear timing wrong, remove it and reset the little gears.

Check your battery voltage first then check your connections tightness and corrosion

You need to figure out what the engine looses when it dies. If it looses spark at the plugs I suggest looking to the ignition module, and if it looses fuel I would look at the fuel pump or the relay. It could also bee a poor ground loosing connection when it heats up too though.