No start on 2006 TJ

Fishtaco

TJ Expert
Original poster
Joined
Sep 29, 2020
Messages
3,750
Location
Perth AU
I am still chasing a fast short cold start rattle that only happens if TJ is left for more than 24 hours, I have tried many different filters so thought I would try a crank no start to see if it is in fact oil drain back or not.
Is there a fuse I can remove to allow starter crank without starting or does the 06 have an anti flood feature (Full gas pedal at key turn crank only)?
My thoughts are that the slower cranking may bring oil up to the top end and then on proper start see whether the rattle is there , I am grasping at straws here with self diagnosis, the fast rapid metallic rattle lasts less than 2 second but I do have a slight tick for a few minutes.

Its driving me mad! once its been started it doesn't happen again even if I turn it off and re start immediately after the dry start rattle? I have read that some JK,s did this from new but not TJ,s.

I have tried to capture the rattle on my phone but just doesn't want to happen when I record lol.

cheers
 
You can remove the fuel pump relay, but there is a chance the remaining fuel in the injector rail may fire a few cylinders briefly...
I could just bridge the solenoid but was looking for an easy out! lol
 
I still think the rattle is just a lifter that is losing it's prime when sitting. It's not really going to hurt anything but turning the motor over to prime it before it fires isn't doing anything but covering there noise to with the starter noise until it gets pumped up which as you've noted takes a few rotations. If the noise bugs you enough, I think you have 3 options:

1) Try some oil flush/cleaner/whatever to see if the pump in the lifter can be freed up.
B- Replace the lifters
III. Get one of those handy dandy oil primers that store oil pressure from the last time it was running and let you manually pressurize your oil system before starting it. Race car guys use those.
 
If I ever want to crank mine without starting, pulling the fuel pump relay is my go-to. But I agree with the poster above that I don't think you're going to get what you want out of this.
 
If I ever want to crank mine without starting, pulling the fuel pump relay is my go-to. But I agree with the poster above that I don't think you're going to get what you want out of this.
I just want to see if the noise is present at less than start up RPM and if its still there after priming the oil up top then cold starting normally. So you dont think a no start prime would pump oil up top because that's all I want at this stage as apart from the ultra fast ultra short rattle it runs perfect.
 
I still think the rattle is just a lifter that is losing it's prime when sitting. It's not really going to hurt anything but turning the motor over to prime it before it fires isn't doing anything but covering there noise to with the starter noise until it gets pumped up which as you've noted takes a few rotations. If the noise bugs you enough, I think you have 3 options:

1) Try some oil flush/cleaner/whatever to see if the pump in the lifter can be freed up.
B- Replace the lifters
III. Get one of those handy dandy oil primers that store oil pressure from the last time it was running and let you manually pressurize your oil system before starting it. Race car guys use those.
I thinks Its too rapid for one or more lifters, the only other advice I get from non TJ mechanics is start up chain rattle due to tensioner drain back but the TJ doesn't have a hydraulic tensioner to fail.
It must be oil related as its 1/4 of a second metallic rattle followed by 3/4 of a second dull rattle.
Got a link to the oil pressuriser?
 
I don't have any specific one I recommend. Never used one, but I know people that used one from Moroso. Different people call them different things depending on their primary use. Here's a video that should make you feel right at home. Bonus points for Skyrine application 😃

 
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Nobody have any ideas?
ASDF124.webp
 
Nobody have any ideas?
Sure, about half a pint of Marvel Mystery oil in the oil for a bit and that will fix it right up. BG makes a product that will also work but I can not for the life of me remember which one it is and now their product selection looks like the pasta sauce aisle in a supermarket.
 
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I had a similar noise in my 2006 LJR and dumped in a bottle of SeaFoam. I am not here to argue the merits or demerits of this product. I used it once. The noise stopped. 'Nuff said.
 
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I ran some Sea Foam in the oil about 500 miles before an oil change in my old XJ. It cleared up a knock or two I was having and when looking through the fill hole on the valve cover, it "looked" cleaner. Probably all in my head but I've done this from time to time in the vehicles I've owned, and it seems to clean things up. I don't recommend this as a regular procedure. I'm just a DIY guy in my home garage.
 
I had a similar noise in my 2006 LJR and dumped in a bottle of SeaFoam. I am not here to argue the merits or demerits of this product. I used it once. The noise stopped. 'Nuff said.
Haha, timing on our posts....
 
The JT and JL both you hold the throttle to the floor, press brake to start, and it'll crank for 10 seconds. I am certain the TJ does not do that... you could maybe unplug the connector to the coil-pack?
 
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Sure, about half a pint of Marvel Mystery oil in the oil for a bit and that will fix it right up. BG makes a product that will also work but I can not for the life of me remember which one it is and now their product selection looks like the pasta sauce aisle in a supermarket.
Before oil change? I have less than 500 miles on this change. I dont mind changing oil again though.
 
Sure, about half a pint of Marvel Mystery oil in the oil for a bit and that will fix it right up. BG makes a product that will also work but I can not for the life of me remember which one it is and now their product selection looks like the pasta sauce aisle in a supermarket.
BG EPR?

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