1994 YJ Cold-Start Problem - JeepForum.com

 
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post #1 of 14 Old 09-25-2012, 05:22 PM Thread Starter
BuckarooBanzai
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1994 YJ Wrangler 
 
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1994 YJ Cold-Start Problem

My 1994 YJ 2.5L is reluctant to start when cold. The battery is charged, alternator works, and the starter cranks. After a few attempts to start, it will try to fire. If it starts, and I drive for a while, it will start again. Now it tries to fire but won't keep running.

I checked for corrosion on the modules/fuses in the box near the battery, and I added a bottle of Heet last time I filled the YJ with fuel.

Any ideas regarding how to fix this issue?

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post #2 of 14 Old 09-25-2012, 05:49 PM
Mark05059
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turn the key to the on position and wait for the check engine light to come on... then try and start it.

1998 ZJ 5.2 Auto

1989 Wrangler Black Bone Stock 2.5l 5spd
/l , [____],
|---L--[]lllllll[]-
()_) ()_)==O=)_)
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post #3 of 14 Old 09-25-2012, 06:00 PM
Bill94
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My 94 yj with the 4.0 is starting to take its time at starting in the morning.

I live where the nights get down to the high 20's in the winter time if that.

back to hard starts in the morning, what if any has other owners done to fix this

problem?
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post #4 of 14 Old 09-25-2012, 10:30 PM
1988Wranglers
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Two things, i'm not sure if the 4 bangers have it but the straight sixs have a choke for cold starting. You simply hit the gas full throttle once and its on ..also have you checked your spark plugs and wires,I changed out my plugs and what a difference it was!
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post #5 of 14 Old 09-26-2012, 06:28 AM
Bill94
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On mine the plugs look good, but I will give that a try.
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post #6 of 14 Old 09-26-2012, 11:06 AM Thread Starter
BuckarooBanzai
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Thanks, Mark. I wasn't waiting for the Check Engine Light.

The plugs are new, and the wires are OK. Depressing the accelerator didn't make a difference.

It appears the fuel-pressure regulator is malfunctioning. I will also get capacitors for the ECU "brain surgery" ( http://www.jeepforum.com/forum/f12/c...rs-ecu-492597/ ). We'll see how that goes.

Thanks, fellas!
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post #7 of 14 Old 10-11-2012, 03:11 PM Thread Starter
BuckarooBanzai
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I replaced the capacitors as mentioned in the "brain surgery" thread. It didn't solve this issue, but then the symptoms are different (I figured it wouldn't hurt to replace the capacitors anyway).

The Check-Engine Light comes on when I turn the key to the "on" position. I still have to wait a few minutes before it will run when I try to start it. The longer it sits between trips, the longer it takes for it to start.

When it finally does start, it runs rough (like it isn't getting fuel), and it takes a while (even on the highway) to run smoothly.

Is this a fuel pump? A relay? Any other ideas?
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post #8 of 14 Old 10-19-2012, 04:55 PM Thread Starter
BuckarooBanzai
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The ASD and fuel-pump relays check out. All wire and connections look good.

With the ignition turned "on", I hear the noise in the engine compartment, but there is no fuel when I depress the valve stem on the fuel rail.

This morning it was chilly outside and it wouldn't begin to fire even with the key turned to "on" for half an hour. This afternoon it tries to fire after a while.

Does this indicate a bad fuel pump? Something else?
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post #9 of 14 Old 10-19-2012, 06:19 PM
1SASjeepster
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On a 1998 ZJ with the V8 in it, the fuel pump module is combined with the fuel sending unit and a "one way" valve. Generally all these are replaced at one time rather than repaired individually. In my neck of the woods, the module costs $300. The "one way" valve is designed to keep fuel in the lines by not allowing it to "bleed back" to the tank after you turn the engine off. If that valve goes out, it does what you are saying BUT you need to check for fuel line crimps or cracks. I am sure if you had a crack, you would know by the smell. Sometimes you can crimp the line and not realize it, of course, this is depending on how you use it.

For the V8, there is a factory procedure to figure out what the culprit is, but I don't think the specs are the same for your engine. If no one "chimes in" with the correct procedure and specs for your motor, than I will post it for you... unless you want me to do it anyway. It is up to you. Good luck and don't worry. We will have you going before winter sets in.

Take care,

Check out "YJ V6 Conversion" if you want to see a frame up restoration of my 1992 YJ.

Check out "WWII Jeep Photos AND Restoration of..." if you want to see the original JEEP in action...
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post #10 of 14 Old 10-13-2013, 02:24 PM Thread Starter
BuckarooBanzai
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Forgot to post a solution to this one...
A distributor wire was faulty.
Thanks for your input, folks!
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post #11 of 14 Old 10-13-2013, 06:08 PM
Que89YJ
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Love the name you took! Lithgow's funniest stuff ever. Trapped on a sub for a west pack for 6 months and I bet I saw the movie 20 times at least! Was it the coil wire to the distributor that was bad?
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post #12 of 14 Old 10-19-2013, 02:23 PM Thread Starter
BuckarooBanzai
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"Yes on 1, no on 2"

I mean, yes that wire.
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post #13 of 14 Old 11-27-2013, 11:35 AM
JeepDerek32
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94 YJ cold start troubles

I have a '94 YJ 2.5l that has been giving me trouble starting in the cold. Block heater works, I have run fuel line anti-freeze through it and I know it's not the battery; I have power, it turns over but consistently will not fire UNLESS the check engine light and shift indicator light are on....I try to start it and after a few cranks, these lights flicker on, I turn the ignition off, try again and pump the gas twice, and it fires up reluctantly. Anyone have any thoughts on what the problem might be?
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post #14 of 14 Old 11-27-2013, 03:10 PM
Que89YJ
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Derek you need to post up to a new thread.
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