My dad has a 87 Ford Ranger w/ a 2.9L V6 w/ 193k miles. Yesterday the truck starting running rough with jerking and a bad skip. No instruments or lights indicated a problem. We drove the truck a couple more miles like that until we got home. Afterward we tried to move the truck and it would not start. The engine became flooded so we let is sit overnight. Today the engine would spin a little then stop. We pulled the plugs and many if not all of the cylinders were full of fuel. We pulled the coil wire and tried to turn the engine over to push the fuel out of the cylinders.

After putting the plugs back in the engine we tried to start it but it stopped again. I have never seen an engine pump that much fuel out of the cylinders. It seemed like the Fuel Injection was continuing to rapidly fill the cylinders with way more fuel than a fully functional engine could use. Any ideas what is wrong. Thanks for your help.

 

Sounds like the fuel pressure regulator diaphram has failed. Unhook the vacuum line connected to the fuel pressure regulator an see if there is fuel present. If so, you need a new regulator. The fuel is being forced/sucked into the intake via the vacuum line from the regulator.

 

"Use Common Sense" you were right on in your diagnosis. We changed the regulator and it came back to life. It doesn't want to idle correctly, but at least it driveable now. My dad is going to take it to a mechanic to see if he can fix it. We don't know what else to do to it. I just wanted to reply to say thank you for your posting. You were a great help. I thought the truck had finally died... But I was wrong.

 

Glas I could help. At least you caught it before you hydro-locked it. I've seen these suck enough fuel thru the vacuum line due to a bad regulator to bend connecting rods.

Also, check your oil. You may need to get it changed due to fuel dilution caused by the excess fuel washing past the rings.