94 explorer won't start periodically

[MRDwpb]

94 Explorer periodically won't start. Engine turns over, but won't start. Later eventually will start(about an hour later). Problem started out less frequent and has become more frequent this past month.

 

[Alec]

i'm thinking its a fuel problem

listen for the fuel pump when you turn the key to "on". if you don't hear it, it may be the fuel pump relay.

could also be an old fuel filter.

 

[Brain]

Could be lot's of things:
1) Fuel - lack or excess of it
2) Spark - lack of it or at the right time
3) Air - not the right fuel to air ratio

It could be lack of fuel, caused by plugged filter, line, injectors, or a bad fuel pump. Fuel problems are a little difficult to diagnose, but there is a port where you can take a pressure reading (looks like an valve stem for your tires, but be sure it is not the air conditioner pressure tap on the A/C lines).

It could be spark. To test, pull a plug (or all of them if you need to be sure), hold it with some insulating pliers (or rubber gloves) so that the body of the plug is touching the engine (or another good ground) while a friend cranks the engine - and look for a spark. The plug wire does have to be attached. The timing is electronic so discount this until all other things have been eliminated. It sounds like your battery and terminals are O.K. because your starter is cranking.

The air/fuel ratio is run by the computer using the mass airflow sensor, the oxygen sensor and some other sensors, but those would be problems that would cause a check engine light to come on, which reminds me...is it coming on?

Better descriptions yield better answers.
(Ex:Q.Hey doctor - when I eat some green things I get gas....what's my problem? -
A.Gas because of something green you're eating.)

 

[dogfriend]

94 Explorer periodically won't start. Engine turns over, but won't start. Later eventually will start(about an hour later). Problem started out less frequent and has become more frequent this past month.

My 89 Ranger used to do this (that is part of the reason I now have an Explorer - it once did this right before a camping trip and we ended up canceling rather than taking the chance of getting stranded)

In my case, I didn't find the problem until it finally refused to start at all. Then I was able to find the problem - the resistance in the coil was way too high so I wasn't getting any spark.

You can check the coil pack resistance pretty easily to rule this out - the Haynes manual has a good procedure in Chap 5 and/or check out this thread:

Coil Pack Resistance

 

[G-Unit]

It's an electrical short in the steering column.

G-Unit

 

[dogfriend]

It's an electrical short in the steering column.

G-Unit

He said that it cranks over but doesn't start. How would a short in the steering column cause these symptoms?

 

[G-Unit]

Please don't ask questions if you don't what you're asking..

 

[dogfriend]

Please don't ask questions if you don't what you're asking..

Actually, I do know what I'm asking, so I will ask again more clearly:

How would a short in the steering column cause a no start condition but still allow the starter to crank the engine?

I can see where an 'open' in the ignition switch might cause this, but not a short.

I read your other post on this:

That ain't the problem


Dundy, I had the same problem about 2 months ago, and no one could figure it out. Sometimes it would start sometimes it wouldn't. I'll tell you what it was. For mine, it was an electrical short in the steering column. Like you said, I thought it had to do with ignition but that was not it. As well I replaced a bunch of parts. Get a home mechanic or someone you know who can check this out. Short in the steering column. One thing to check for. When you start the car, the "Check Engine" light should flash on. If it doesn't, you got a problem.

G-Unit

I do not understand how this 'short' would allow the engine to crank but not start. Can you explain more clearly?

Thanks
Dogfriend

 

[G-Unit]

A short in general still allows power to something, but a shorted wire fails to allow full function to ignite or catch. Its like a cd receiver. Its on and hot, but it ain't playing.