Hi all,

First off give you a run down of the vehicle. It is a 2006 Explorer with the 4.0 and around 89,000 on the odometer. Around a couple weeks or so ago the wife said the explorer was hard to start one evening and it has been like that ever since. It cranks for about 5 seconds and then fires. So far it has started every time since this issue began. This is really the first issue we have ever had other than the radiator replacement a few years ago.

Any suggestions on where I should start looking, it would be greatly appreciated! If you need more info please ask. Thanks again!

 

Any other symptoms like rough running for a few seconds or more? Is it hard to start after it sits for a long time, short time, every time, when the engine is cool or when hot?

Try turning the key to ON, then OFF and repeat this a few times before you try to start it. If you have a fuel pressure gauge, put it on and check the pressure when trying to start it.

 

The only time it is not hard to start is after a long drive. Today was around 100 miles and through the mountains. After we got to our destination and was there for around an hour, we left for a quick trip to the restaurant and it started fine. It is only after setting overnight is when it is hard to start.

It has only ran rough one time and that was after a 25 minute drive the other night and it was in the driveway at an idle. The rpms would fluctuate 300 or 400 rpms. It didn't due that before or since.

Also it does have the original battery and the float voltage is right around 12v. I had read somewhere that the crank position sensor could possibly cause an issue like this. I don't have a fuel pressure gauge. I can go to advance or auto zone and get one if needed. Where would you connect it to or in line at? Thanks again!

 

Wow, if you have a 2006 with the original battery, replace that battery before spending much time troubleshooting other things.

A bad crankshaft position sensor will cause a no-start condition, not just a long crank before starting.

-Rod