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Discussion Starter · #1 ·
Ok guys, im new to jeeps but not new to cars, im looking for some direction from some people with more jeep experience then i. So my jeep will turn over all day but wont start. Currently it does not throw any codes, fuel pump kicks on and makes almost 50psi. I dont have a noid light but if i put my fingers on the injectors i can feel them firing. Also after awhile of cranking i can smell that its flooded. I guess i cant 100% rule out some fuel related issues but im pretty sure thats not it. So i started checking ignition, I am limited on tools(i know, i am young though and my collection is just starting) I know its getting signal to the coil at minimum so I figured its cheap ill start with coil, cap, rotor, wires and plugs. All that is done now and it still will not start. Any ideas? Thanks in advance for any advice.
 

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Did you pull a plug, ground to the block and check for spark. I would suggest a spark tester, but you said limited tools.
 

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I had the same problem about 2 months ago. First I changed the coil and got nothing then I changed the crank position sensor and she fired right up. It was about $70 from advance auto and only took 5 minutes to change. Its located on the bellhousing on the driverside near the top right where the bellhousing meets the block.
 

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Discussion Starter · #4 ·
I haven't checked for spark at the plugs yet, a spark tester is on the list of tools to buy, along with an ohm meter. Is there a test to check if the crank position is good? Also would it fire the injectors if the crank position is bad?
 

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You can test out the CPS with a ohm meter. Unplug the one end see if you are receiving anything on it. Thats what my Hayens says anyways.
 

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I haven't checked for spark at the plugs yet, a spark tester is on the list of tools to buy, along with an ohm meter. Is there a test to check if the crank position is good? Also would it fire the injectors if the crank position is bad?
You will get fuel but no spark.
 

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One thing to check for too is water in the fuel. I had an almost identical situation about 6 months ago. I had all of your same symptoms, and it ended up that I had water in the fuel. I siphoned the tank and added fresh gas with some stabil, and it fired right up.

Just a suggestion.
 

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I notice my 97 4.0 won't start sometimes intermittently.... Crank steadily for 5 seconds and won't even sputter to start... then turn the key off and try again and if fires right up. Would a crank sensor act like this before going completely bad?
 

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I notice my 97 4.0 won't start sometimes intermittently.... Crank steadily for 5 seconds and won't even sputter to start... then turn the key off and try again and if fires right up. Would a crank sensor act like this before going completely bad?
That sounds more like the check valve in the fuel pump is leaking and allowing the fuel that is supposed to remain up next to the fuel injectors after the engine is shut off to instead drain down and back to the gas tank. Turning the key off and back on again triggers the fuel pump again to send more fuel up to the fuel rail. When the check valve starts leaking badly enough, it can take multiple on-off-cycles with the ignition to get the fuel pump to run enough to get fuel all the way back up to the engine's fuel rail that the fuel injectors are connected to.
 

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That sounds more like the check valve in the fuel pump is leaking and allowing the fuel that is supposed to remain up next to the fuel injectors after the engine is shut off to instead drain down and back to the gas tank. Turning the key off and back on again triggers the fuel pump again to send more fuel up to the fuel rail. When the check valve starts leaking badly enough, it can take multiple on-off-cycles with the ignition to get the fuel pump to run enough to get fuel all the way back up to the engine's fuel rail that the fuel injectors are connected to.
Ok Thanks Jerry! That makes sense to me. Sorry, I wasn't trying to hijack your thread "NeedAWD"..... Thought I was on topic. Good Luck getting your jeep running.
 

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You don't need a "spark tester" to test for spark at the plugs, all you need is a screwdriver - Phillips preferred.
Remove the wire from the plug, poke the screwdriver in the end of the wire - hold the screwdriver near to the engine, have someone crank it. Be sure to hold the screwdriver by the insulated handle - or you'll personally verify it has spark.

You should have a crispy thin blue spark at least 1/4" long jump from the screwdriver to the engine. (Or your eyes will light up.) If you crank it, and your helper holds it - you can tell it's OK by his scream.)

If red or yellow, do the same thing with the coil wire - pull the end from the distributor.
Next - ground the screwdriver with a wire, poke it in the center tower on the dist cap - If blue now replace coil wire.
If still red replace coil.

No signal from the Crank Position Sensor will kill BOTH spark AND triggering of the injectors. No fuel AND no spark.

A noid light costs about $5.00 for the one that fits Jeep. The whole kit (6 types) is less than $20 on Ebay.

Before replacing the CPS, try unplugging then reconnecting the connector to it - on the harness going to it - behind the valve cover. Often it's just a touch of corrosion in that plug. Opening and closing the connector often makes connection again.

The computer must "see" the CPS pulse in order to close the ASD relay - else no spark and no injector trigger signals.


the
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Discussion Starter · #14 ·
Alright, got it running, crank position sensor was the issue, I cleaned all the battery terminals and connections while I was at it. It is running like a champ now, thank you guys for the help
 

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Alright, got it running, crank position sensor was the issue, I cleaned all the battery terminals and connections while I was at it. It is running like a champ now, thank you guys for the help
I was having the same issues on my 99, and it also turned out to be the crankshaft position sensor. At least it's an inexpensive and easy fix.
 

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Okay. I REALLY need help. I have a 1997 Jeep Wrangler 2.5 cyl 230,000 miles. Ever since I bought it, it has had a tough time starting. It would crank for about 4-5 seconds and then sputter a bit and start right up. It continued to get worse. A month after I bought it, it wouldn't start one morning. It would crank all day but not start. I got the fuel pump replaced and it worked for two more weeks with the same initial problem (crank for 3-5 seconds and sputter and then start). Then it quit again. Crank all day no start. So I took it back to the shop and got the fuel pump and fuel pump motor replaced AGAIN. It's been two weeks now and it's about to do it to me all over again.

purchases:
new spark plug wires. two new fuel pumps. I checked the spark plugs, they all have perfect spacing and all spark perfectly.

I have heard that a new camshaft timer would fix this but I need more conformation on that theory.

ALSO NEW PROBLEM AROSE TODAY... jeeps...:
my engine just started making a ticking noise. it is constant and does not go away. It is not that loud and is not a "knock". I CANNOT feel it, but I CAN hear it. My exhaust manifold is cracked and I have a new one in the garage ready to be installed. Could that fix the ticking problem?

I have the first jeep my family has ever owned, so we don't have a lot of jeep experience. I LOVE my jeep and I couldn't ever get rid of it. please please please PLEASE help.
 

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As a Jeep Wrangler owner for 12 years I'm trying to pick up as much information as I can about possible future problems.
What is a noid light and how is it used? Growing up in my Dad's garage back in the 50's & 60's I've heard about and used several types of lights but never a noid light. Maybe I've used one but didn't know what it was called.
Thanks for enlightening me on that.
 

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DCM-0340 Code (camshaft position sensor)

I was driving about 35 mph down the road and the Jeep just quit. The check engine light did come on. (1997 Wrangler TJ 2.5 5-speed). The DCM code gave a 0340 camshaft position sensor reading. I replaced the sensor, still no start. It will turn over, but will not fire. I replaced the rotor and still no start. I removed the distributor cover and had my brother watch the distributor as I attempted to start the Jeep, the distributor did not budge. I pulled the distributor and the pin was still in place. I looked inside the distributor hole and did not see anything out of the ordinary.

My question: If the crankshaft position sensor is faulty would it cause the distributor to malfunction? To not rotate?

Or if the PCM is faulty would this also cause the distributor to not move?

I could sure use the help here, I've only owned the vehicle for 3-weeks.
 
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