87 Ranger. I NEED HELP ASAP.

[ross101]

87 Ford ranger. The motor runs for about 20 seconds then will both down and cut of even if you give it gas. throttle positioning sensor is good and maping sensor is good also. Not really sure where to go from here. I have replaced the fuel line and fuel pump. Also has a new fuel tank. When truck cuts off there is still gas on the fuel rail with a lot of pressure. I need help ASAP

 

[Sams01XplrSprt]

welcome ross

 

[ragajungle]

Welcome.
Do you smell gas strongly? does it run poorly before it clunks out? If so it may be a FPR (Fuel Pressure Regulator). a quick check would be to locate it (a chrome vacuum device located on the fuel rail) and carefully pull the vacuum line off the top. If there is any fuel in the line it is bad and needs to be replaced.

how does the airfilter look?

 

[tgreene92]

could be lots of things, fuel relay issue, lack of spark, timing off, dirty or bad injectors, lack of air. list goes on... is there any other symptoms? have you done any recent work or maintenance?

 

[tgreene92]

Welcome.
Do you smell gas strongly? does it run poorly before it clunks out? If so it may be a FPR (Fuel Pressure Regulator). a quick check would be to locate it (a chrome vacuum device located on the fuel rail) and carefully pull the vacuum line off the top. If there is any fuel in the line it is bad and needs to be replaced.

how does the airfilter look?

congrats on your thousandth post, not sure if you realized or care, lol.

 

[BrooklynBay]

Welcome to this forum! I've moved your thread into the Ranger section.

 

[Tbars4]

What motor do you have?
Posted via Mobile Device

 

[tmwalsh]

Given the age of your truck, I would take a look at the actual ignition 'switch' mounted on the steering column. They can start to come apart with age as they are held together with a pot-metal 'crimp' that weakens. That would/could cut off the power to the TFI module, and coil. You could also try moving the key closer to 'start' or 'off' to re-position the contacts a little inside the switch. Mine got to where you could start the truck fine, but if you let go of the key it would turn itself off...
tom