2000 Mercury Mountaineer
5.0L V8 w/130k on the clock.

We had a cold snap pass through this week and one morning my mom's Mountaineer wouldn't start. I came home after school that day with the intention of testing the coil, but it ended up starting. Dad has been driving it this week with no problems until today. It was raining really bad, he started it up and got on the road with no problems. While stopped at a light it started to stumble and then it just died, and wouldn't start back up. I pulled him back to his office and we left it there for the night. I need a few tips on where to start diagnosing the problem. I know how to test the coil. Is there a way I can check to see if it's getting fuel? It's been pretty well maintained since they got it. Plugs/wires are fairly new along with air/fuel filters. Any help at all would be great.

 

ok first off can you hear the fuel pump? if yes bring a fuel pressure gauge with you to check the pressure.
if you cant hear the pump then check the inertia switch, and is the pats light coming on?

 

Does that thing have a distributor or coil packs? Either way, inspect them carefully for cracks, arcing, and carbon tracks.

 

its got the coil packs and wires.

 

The first thing you need to do is buy an OBDII code reader. Otherwise, yer guessing and so are the good folks attempting to help.

 

Many auto parts stores will read your PCM for free if you can get the vehicle to the store.

 

When vehicles stumble and die its most likely a fuel issue 90%+ of the time. If it shuts off like someone turned the key off its usually a spark issue. By the sounds of it, it is most likely the fuel pump. Have someone jump in it and crank it for about 30 seconds, if it starts it starts. If it doesn't shut the key off, let the started cool a bit then have somebody crank on while someone else hits the fuel tank with an open hand, kick it or even use a hammer. You can hit the tank quite hard before you run the risk of denting it.

Also another trick you may want to try is spraying air intake cleaner into the throttle body, if it starts it is a fuel issue.

If it just dies, a code reader will likely do you no good in this situation because they rarely throw codes from just dieing. It's not a bad thing to have but it will likely do you little to no good in this situation.

 

you shouldnt crank more than 15 seconds each time. thats a quick way to burn up the starter.