94 Explorer cranks but no start, details inside Thanks for any help

Since this is a '94 did you check the positive battery cable? They can deteriorate inside the insulation and look fine on the outside. Are the connections all clean?

I don't know if the brains on the '94 are the same as the '97 but on my '97 it was doing exactly what you are describing. It turned out to be a bad battery. Two of the cells were a little weaker than the others. Apparently there was enough juice to turn the starter motor and crank the engine but not enough to make spark. I also cleaned the contacts on my crank position sensor so that may have contributed to the solution too.

If you have a good, fairly new battery I suggest trying it.

Reply to
Ulysses
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It's true that a failing battery/poor connection can cause strange symptoms. I too had this on a Dodge Caravan- seemed to be cranking fine, sounded normal, but messed up the computer.

-Paul

Reply to
Paul G.

Hey Ulysses

Thanks for the info. Interesting handle you are using as that is my first name. Anyway...

Just had my battery tested and it came back OK even under load. BUT the positive cable looks bad, so I will replace it. Also, I will pull the crank position sensor and clean the contacts. This is the unit that is bottom front center, right?

A further ellaboration might be helpful. When I turn on the ignition I do not hear the fuel pump run. I hook up the code reader and cycle test then I hear the fuel and the car will then start. Plus I can hear the fuel run when I turn on the ignition.

What would the cause the fuel pump to cycle when connected to a code reader (during test cycle), but not when the ignition is turned on. Also, It seems to happen when the weather is warm and I can't remember it happening when the weather is cold.

Thanks

Jim

Reply to
J Adams

Paul,

The battery tested fine, so I'm going replace the positive cable. It does seem erratic so maybe it is computer related as a result of poor connections. Would warm weather be a factor?

Jim

Reply to
J Adams

Huh. My name is Jim too. I use Ulysses from Homer's story The Odyssey.

I'm not sure where it is on the '94 but that's where it is on the '97. Pretty easy to get to.

My understanding up to this point was that you had verified that you have adequate fuel pressure. You DID test it, didn't you? At this point I have to ask: Did you push the fuel shut-off reset button?

When mine would not start I tested the fuel pressure and it was OK. There was a wire for I'm not sure what attached to the coil pack that looked damaged so I cut out the damaged part and resoldered it. Nothing. I tested the voltage at the coil and it tested OK. The fuese were all OK. Everything the Hayne's manual said to check tested OK. The battery even

*seemed* to be OK as far as the voltage and ability to accept a charge were concerned. My battery connectons were clean and tight. Sometimes the car would start and sometimes not. It seemed to be happening more often when it had been sitting for a day or so. I also tried to determine if the problem was fuel pump related and was happening more if it was parked facing downhill. Inconclusive. I cleaned the contacts on the crankcase position sensor and replaced the battery and the problem has not reoccured. But this was a '97 and the '91-94s are notorious for bad positive cables.

In any case if you can't hear the fuel pump cycling when you turn on the key then I'd start with the ignition switch, go to the pump relay, check the battery and cables and connections, push the fuel reset button, and make sure power is getting to the fuel pump. I had a bad ignition switch on my '91 but I don't remember what the specific symptoms were. It was probably obvious. I also suggest that you pull out all ignition and fuel pump related fuses, check and clean contacts as needed, and reinstall them. Maybe you just have a dirty connection somewhere.

Reply to
Ulysses

Yes the fuel presure was OK, went to 40psi and dropped to 38psi and held at 38psi.

Fuel shut-off reset button? Didn't know there was one, what does it look like and where is it? Can't find it in the Haynes manual.

These are the exact symptoms, except sometimes it has happened when I went into the store and came back out and wouldn't start (3 times).

Just replaced the positive cable. I'm curious how the crankcase position sensor would affect it. It did not show up on the code reader test cycle. However, I'm going to Mexico next weekend so better safe than sorry so I will clean the contacts anyway. Even though the battery test out OK I'm willing to replace it. Yes?

Replaced the fuel pump relay, just in case, and have now pulled, clean, and reinstalled all relays.

I keep coming back to what would cause the fuel pump to cycle when the code reader test cycle activated and not the ignition switch. Then once the fuel pump cycled via the code reader the fuel pump would cycle with the ignition switch.

Thanks again

Jim

Reply to
J Adams

An ignition switch issue can show up as all sorts of things. On my wife's '92 Acura Legend, the car would start, but it would shut off as soon as you let go of the key. The grease in the switch had gotten old and was acting as an insulator on some of the contacts, turning off the power to the engine and computer when you let go of the key. I cleaned the switch with some contact cleaner I got at an electronics store and the problem went away. My wife insisted on a new switch (just the part with the contacts and the cable to the bulkhead was $100) so I replaced it.

Reply to
Mike Iglesias

I had a starting problem on my '91. Got progressively harder to start till finally it would not start. The problem was finally tracked down to the group of wires that are located near and under the positive battery post. Two of the wires were corroded to the point of failure. A new length of wire was spliced in and the problem was solved. Hope this helps John Normile

Reply to
Camperken

You can rule that out. If the fuel shut-off is tripped it won't start at all until that is reset.

-Paul

Reply to
Paul G.

Like Paul said, if you have fuel pressure it's not the reset switch. FYI it's located just under the top of the carpet on the front, passenger side. I think the button is red.

If you are going to drive it to Mexico can we assume it's been starting reliably?

If the car's computer cannot read the crankcase position it will not allow the ignition to spark. I don't know how to test the sensor but I'll bet they don't cost a whole lot to replace. If you don't get it from Ford anyway.

On a newer car I would not do the "shotgun" approach and start replacing everything under the hood but we are talking about a 13 year old truck here so IMHO it might be reasonable to replace a few suspected items that have not proven defective but could possibly cause problems in the near future. When my '91 was overheating I replaced the radiator, radiator cap, fan, fan clutch, water pump, and thermostat. The water pump still seemed OK and the radiator was not leaking but with about 200K miles on it I felt it was about due anyway. No more overheating problems anyway.

Come to think of it I had a '93 Escort Wagon and when the battery had reached the end of it's days the engine would crank but not start. Kinda makes you long for the days when engines had distributors and no brains and manual transmissions so you could push-start them. I parked my ol' '61 VW on a hill whenever I stopped it so I could just roll down to get it going ;-). If there was no hill the thing was so light I could push it myself and jump in, pop the clutch and be on my way.

It's been a while and I'm getting kinda old but if I remember correctly on my '97 when I disconnected the crankcase position sensor and reconnected it the fuel pump cycled. Maybe. And of course a '97 is not a '94. Same engine though.

Reply to
Ulysses

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