1995 Ford Explorer 4WD Stick - occasionally won't start

1995 Ford Explorer 4WD Stick = 178,000 miles

I am the first and only owner of the above car. About 5 years ago I started having the problem that my car wouldn’t start sometimes (generally when it is hot). At first it only happen a couple of times a year. Now it happens a couple of times a month. It always starts first thing in the morning and if the car has been sitting for 6 to 8 hours – no problem. I run in to problems on hotter days generally when I am running back to back errands from one place to another. My mechanic hasn’t been able to zero in on the problem. I’ve even left it with him for a week to drive around (the car is always working when I drop it off to get worked on so it is hard for them to identify the problem). Lately, I’ve been popping the hood and firmly pounding on the power distribution box and the fuses inside. Someone told me to do this and 8 out of 10 times it seems to work. On the times that it doesn’t, I leave the hood open and after the engine cools a little, the car starts again. I’ve had the battery, ignition/starter checked. I’ve had the fuses cleaned and checked. I’ve also noticed that as I turn the key before the final turn to start the engine, there is another noise of something being “turned on.” 100% of the time, when I hear this noise, the engine starts. 100% of the time when I do NOT hear this noise the engine does not start. Someone told me they think this is the fuel intake switch. My mechanic and I are at a loss of what to try next. Any thoughts?

That someone is headed in the right direction.

When you turn the key to the ON position, do you hear the fuel pump making a buzzing noise for a couple of seconds? If not, it may not be priming the fuel system.

The next time it doesn’t want to start, spray a little starting fluid in the throttle body. (remove the air intake hose)

Attempt to start the engine. If it starts then dies almost immediately, there likely is a fuel pressure problem.

Perhaps a worn fuel pump, plugged fuel filter, faulty fuel regulator or injectors.

If there is fuel and no spark, then obviously it’s an electrical problem. Perhaps an ignition system fault or bad coil pack/plugs or wires.

I do hear a noise in the ON position – I’m not sure it is a buzz but it sounds like something has been turned ON. When I hear that noise, I know it will start. When I don’t hear it then I know it won’t.

I will ask my mechanic about the points you’ve brought up to check. Thank you for the input!

If anyone else has any thoughts, please post them!

Open the hood. Stand near the left fender. As someone turns the ignition switch from OFF to ON, see if you can locate the buzz. You can place your hand on the power distribution center box to feel for the buzz. If you can locate the source, you can tell your mechanic. FYI: the fuel pump relay is in the power distribution box.

Here is a thought, I had an '89 ford PU with the same problem - it would start in the morning, but it was hit or miss if it would start after I got to my destination and then tried to start it again - I had it towed to the dealer on several occasions and it always started for them - I no longer trusted the truck as it left me stranded a bunch of times and at wits end I finally called my local mechanic who replaced the ignition modulator and I never had a problem after that. I wrote a nasty letter to the dealership as my local mechanic seemed to know immediately what the problem was, and they ended up sending me a check for the part + labor…

I have always subscribed to the logical approach to car repair. There is always a question of whether to troubleshoot a problem down to a defective part or just replace parts on probability and suspection until the problem is solved. If the mechanic has superior knowledge connecting a specific problem with a part, i.e. igntion shutoff with TFI ignition modules, (s)he can save you a lot of expense on diagnostic fees. But sometimes the cost of replacing good parts can exceed the cost of superior troubleshooting and a single part replacement.

One difficulty with an intermittant is that troubleshooting is hard to do if the problem is not present. So changing out parts becomes the only solution. Here a savy mechanic can pick the most likely candidate and try and try again and again.

Yes I agree, replacing parts until you get it right can be expensive, and I usually try to narrow down the problem with what limited expertise I have - I probably should have been more specific - when I called the local mechanic and described the problem, he asked me what the year/make/model was…when I told him he said “bring it in, I know what the problem is”…which was why I was a little peeved at the dealership…if the local guy down the street knew what the problem was over the phone I would have thought Ford would have dealt with it before…

I was thinking that if it’s turning over but just not firing up ask if it could be vapor lock in the fuel line or carb or fuel injectors. if it’s not doing anything maybe the nuetral safety switch.

Thanks to everyone who has responded to this problem. My car is at the mechanic today and for the first time, it did not work while in his possession. Finally! At least he no longer thinks I’m crazy. The car was hot when I got there, it started a couple of times, then didn’t start a couple of times, then started again with him at the wheel. I will print out this latest list of advice and add it to what I’ve already given him. Today I think he is focused on the power distribution box, the fuel pump relay (which he has replaced before) and the fuel pump itself. I will report back on what does/doesn’t work.

We did replace the power distribution box (found one at a junk yard), a relay and a about 6 wires. We did not replace the fuel pump. It’s been about a 10 days now and I’ve not had any problems so far. However, the weather has been on the cool side, so I am still somewhat aprehensive that it is really fixed. We’ll see what happens when it gets warmer. If I don’t write back, it means that the above mentioned parts replacement worked.