I can walk out to the truck, stand outside of it , insert the key in the ignition switch, and start the engine in 1-2 seconds. It idles well, although it goes from low RPMs to high RPMs, while sitting and idling. Shut the engine off, wait a minute, try to restart, and the engine cranks and cranks until it almost starts to wear down the battery. Then if you get in the vehicle and hold the throttle wide open, it will start, like a flooded engine and after coughing and sputtering, will return to a somewhat smooth idle. Code reader says 15. Can't believe that a coolant sensor could cause this problem. I'm leaning to the FPR. Any thoughts?

 

The only way to find out if its a fuel issue is do a fuel pressure and leak down test.

 

you would be surprised on the coolant sensor. But, if you want to spend more money first

 

Fuel pressure is 58 PSI. Pulls down to 55 after 15 minutes. Makes me think fuel filter is a little plugged, and maybe having a vacuum issue as vehicle is loping after starting and idling. Going to change filter.

 

I believe the fuel pressure is ok, 58 is a hair low but thais what mine is and I have no issues. vacuum gauges are cheap. could be that.

 

Have a vacuum gauge, just hadn't bothered to try it. Also gonna do the propane test. Have had problems in the past with the Vac 4WD actuator under the battery, having a bad diaphragm. Gotta check that too.

 

Update! Did vacuum test, propane test, smoke test. All results were negative. Replaced the coolant sensor,,,problem solved. Had a hard time locating sensor and a harder time replacing it. It's tucked in behind the A/C compressor, in the intake manifold next to the gooseneck. Removing the compressor was the only way that I could get it out. Also got a further education. Believe the code reader. I guess you can teach an old dog new tricks. Thanks for all the help and suggestions.

 

And other people, sometimes LOL

 

Glad you figured it out.

 

Very impressed by what the people on here are knowledgeable about their vehicles. You are full of lots of information, because of your own experiences. My Daddy told me one time that you can learn a bunch more from listening to an old man than you can from books, if,,,,,you listen to him instead of talk. You proved it to m, and I'm forever grateful. If you ever need an answer about your heating system, or your refrigeration, or air conditioning systems, just ask. Spent 40+ years doing service and repair on these systems. Just not savvy on vehicles, as I always paid to have them repaired. Now that I'm retired, I have lots of time and not as much money, so I am inclined to try and do my own repairs. Thanks again for your help.