TJ won't start and I've tried everything

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Floridajeepin

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May 14, 2024
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Tampa
2006 jeep wrangler 4.0l manual 202k miles

The engine is cranking and not turning over..

Battery is new and was tested at AutoZone today it is perfect

Recent changes as of today
-new spark plugs
-new starter
-new coilpack
—-tested another new one as well to verify it wasn’t bad coilpack
-new cam shaft sensor
-new crank shaft sensor
-fuses are good and even swapped those too



completely stumped

PLEASE HELP!!


All connections are good



Jeep truly stands for “just empty every pocket”
 
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Fuel to the rail?
Have you put a timing light on a plug wire or verified spark by pulling a plug wire and sticking a bolt or something in the wire and holding it about 1/8 inch from ground while someone cranks it? Should be a nice fat spark...you might want to wear a glove to avoid getting zapped.
The engine needs fuel, air, spark to fire and decent timing to run right.
One of those things is missing and you need to know which to fix it.
 
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Welcome to the forum.

Possibly fuel pump. One test is to have someone turn key to accessory while your under jeep by fuel tank and see you can hear it pump fuel. Look up in the forums for other ways to test it.

I'm sure there will be others along to help out.
 
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Fuel pressure?

Also, a stuck IAC will cause this. Slightly depress the gas pedal while cranking and see if it starts. If so, IAC is stuck closed.
 
TokenJo said:
Welcome to the forum.

Possibly fuel pump. One test is to have someone turn key to accessory while your under jeep by fuel tank and see you can hear it pump fuel. Look up in the forums for other ways to test it.

I'm sure there will be others along to help out.
Click to expand...

You can turn the key on and just check at the fuel rail for pressure. There's a Schrader valve on the rail. Pull the cap and give the pin a quick push.
You should get a healthy squirt of gas.
 
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Mhass said:
You can turn the key on and just check at the fuel rail for pressure. There's a Schrader valve on the rail. Pull the cap and give the pin a quick push.
You should get a healthy squirt of gas.
Click to expand...

Figured there were other tests. Sounds like fuel isn't getting to the engine with it cranking. Could be almost anything. I would start with fuel.

This was in the how to guide section of the forum for later model TJ's.

https://wranglertjforum.com/threads/how-to-check-fuel-pressure-on-a-2003-and-later-4-0.11793/
 
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You need fuel, air, & spark. Above are good things to check.

Check your air intake all the way to the TB too. If an animal got in there and built a nest, you'd starve the air supply. ('tis the season of animals nesting...)
 
Mhass said:
Fuel to the rail?
Have you put a timing light on a plug wire or verified spark by pulling a plug wire and sticking a bolt or something in the wire and holding it about 1/8 inch from ground while someone cranks it? Should be a nice fat spark...you might want to wear a glove to avoid getting zapped.
The engine needs fuel, air, spark to fire and decent timing to run right.
One of those things is missing and you need to know which to fix it.
Click to expand...

Plug wire on a 2006??
 
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Floridajeepin said:
The engine is cranking and not turning over..
Click to expand...

Can you elaborate on what that statement means to you?

Is the starter rotating the engine and it won't fire or you hit the key and nothing happens?

The very first thing i would do is pop off the plastic intake tube and use some starter fluid while cranking. If it tries to start it is fuel related if it doesn't it is spark related.

The pcm on those jeeps like to die.if that is the case you need a @Wranglerfix pcm.not a reman pcm
 
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My 2004 had the same/similar problem a month or two ago. Not saying that this is your problem but mine was the cam and or the OBDA, cam and the OBDA had broken gear teeth.
 
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dvngdg said:
Plug wire on a 2006??
Click to expand...

Oh, damn! Sorry, I just reverted to the old days when everything had a distributor. I see no schrader valve on the fuel rail too. I guess I just need to stick to old stuff.
But still- verify fuel, air, spark and that's 99.862 percent of non-mechanical issues covered. Timing can be an issue but, if you cover the ECM, you have that covered.
Apologies for misleading you. I'll shut up now.
 
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Let's be clear the basics are spark, fuel, compression and timing.

Racetronix sells adapters for the fuel rail to add a Schrader valve or do what I did and just permeantly installed a gauge on the rail (and mine is a 97 so I left the Schrader for bleeding off pressure and double checking with my regular gauge.)

-Mac

IMG20240330184511.jpg
 
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