What did you do to your jeep today?

The lightning bolt is for the TPS (throttle position sensor) on the CRD anyway. My CRD got that light while it was loaned to a friend. One LOST thread mentioned the computer gets confused by throttle movement at startup. Dealer cleared codes and never did it again.

turblediesel said:

The lightning bolt is for the TPS (throttle position sensor) on the CRD anyway. My CRD got that light while it was loaned to a friend. One LOST thread mentioned the computer gets confused by throttle movement at startup. Dealer cleared codes and never did it again.

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I wondered about that but there was no check engine light or TPS code set. It will be interesting to see what the diagnosis is. Air or Fuel?

I got the Jeep towed finally at about midnight. It’s at the shop with the key in the key drop. I’ll report back on Monday when I know more.

lfhoward said:

Yup, the first thing I did after getting home last night was order new hardware for the shocks and sway bar links since it is clear that the old is going to be destroyed. :thumbsup:

I will see if I can find Free All in my area. Is this an order it online kind of thing or is it at HD/Lowes/Ace?

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I usually get it at Auto Zone, but is available online too.

lfhoward said:

I wondered about that but there was no check engine light or TPS code set. It will be interesting to see what the diagnosis is. Air or Fuel?

I got the Jeep towed finally at about midnight. It’s at the shop with the key in the key drop. I’ll report back on Monday when I know more.

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Hate to say it but that sounds like water in the fuel. Did you gas up right before it happened?
Hope Im wrong.

Johnny O said:

Hate to say it but that sounds like water in the fuel. Did you gas up right before it happened?
Hope Im wrong.

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No, I had between 1/3 and 1/2 tank of gas when this happened. I did an oil change the previous day but never got anywhere near the fuel system.

lfhoward said:

No, I had between 1/3 and 1/2 tank of gas when this happened. I did an oil change the previous day but never got anywhere near the fuel system.

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Whew. That's good. 'lectric gremlins are far less scary. 'Tis the time of year for water in the fueling station pumps is why I asked.

Johnny O said:

Whew. That's good. 'lectric gremlins are far less scary. 'Tis the time of year for water in the fueling station pumps is why I asked.

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I suppose my fuel pump could have bit the dust. Still waiting on a diagnosis from my shop but they are looking at it today.

lfhoward said:

I suppose my fuel pump could have bit the dust. Still waiting on a diagnosis from my shop but they are looking at it today.

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I have a diagnosis from the shop.

The #5 cylinder has 0 compression. They say the exhaust valve spring is broken.



Who here has any experience replacing valve springs?

Went for a drive in the mountains yesterday - also went past one of the local dams as they just opened the flood gates a few days ago - lots of water coming out of there!

lfhoward said:

I have a diagnosis from the shop.

The #5 cylinder has 0 compression. They say the exhaust valve spring is broken.



Who here has any experience replacing valve springs?

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Shoot - any idea if the valve kissed the piston?

lfhoward said:

I have a diagnosis from the shop.

The #5 cylinder has 0 compression. They say the exhaust valve spring is broken.



Who here has any experience replacing valve springs?

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derekj said:

Shoot - any idea if the valve kissed the piston?

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Pull the plug and get a boroscope down there before you waste your time trying to replace the spring. See if the piston is damaged. Seems like you'd have to replace the valve too. That means pulling the head.

Oh man, didn’t think of that. The Jeep is still at the shop. I can ask them. I hope the valve stem keepers stayed on and the broken spring limited the travel of the valve into the cylinder.

I didn’t hear any weird metallic noises when this happened, or when I tried multiple times to start the engine. Not sure if that means much.

Came across this tool for the 3.7 to be able to remove valve springs without taking the head off. Has anyone used this? Thoughts? The YouTube video shows how it works.


Of course it relies on air pressure to keep the valve in place while removing the spring, and my cylinder has no compression when the valve is open. Not sure this would work for my use case.

Question to anyone who has worked on 3.7 cylinder heads. Clearly a broken valve spring could cause a valve to stick open. Would a rocker arm coming off do the same thing? Or would the valve be stuck closed if that happened? The reason I ask is that I have heard about rocker arms popping off in the 3.7 before. South Main Auto has a 2-part series on that.

lfhoward said:

Question to anyone who has worked on 3.7 cylinder heads. Clearly a broken valve spring could cause a valve to stick open. Would a rocker arm coming off do the same thing? Or would the valve be stuck closed if that happened? The reason I ask is that I have heard about rocker arms popping off in the 3.7 before. South Main Auto has a 2-part series on that.

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Usually the rocker falls off after the spring breaks and the valve drops.

It really depends what's broken, if you are really lucky you may be able to just replace the spring. You need to see if the valve is still free to slide in its guide, put no. 5 at the top of its stroke before you start otherwise it will dissappear down the hole when you remove the broken spring.
If its tight in the guide then unfortunately it's been hit and bent, a damaged rocker arm is another sign of impact.

started the engine for first time after installing and getting valve seats upgraded.
I bought this Liberty running on 5 cylinders, when I looked in the bad cylinder with camera the valve seat had dropped and shattered into pieces, destroyed the piston and rings, I had multiple pieces in the intake manifold.
I found another engine but I did not want to have this issue again, so I had the valve seat upgraded, they undercut 8-11 thousands, almost 2500 into this engine, did all the work myself except for the head work.
Also replaced tie rod ends, lower ball joints, upper control arms, way too much cleaning to get rid of dog hair, now I need to get it smogged and insured, like I really need another car.
I just got rid of a 4Runner because I have too many cars, and now I will be backup to 4 cars again.

lfhoward said:

Question to anyone who has worked on 3.7 cylinder heads. Clearly a broken valve spring could cause a valve to stick open. Would a rocker arm coming off do the same thing? Or would the valve be stuck closed if that happened? The reason I ask is that I have heard about rocker arms popping off in the 3.7 before. South Main Auto has a 2-part series on that.

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If the spring is broken then the valve is not sealing hence no compression in the cylinder and the rocker would probably fall off. I'd think you'd hear things hitting if it dropped enough. A rocker coming of would close the valve (been there). If the valve seat failed it could be slightly open and little if any compression. Seems like you should have a cylinder specific misfire code. Seems like the keepers and spring pieces would have come off too.

If the valve is slightly open and the spring is broken, then you can use a tool that hooks over the cam and allows you to compress a new spring onto the valve stem. This is only possible if you can grab the valve stem and pull on it while you pressurize the cylinder to keep the valve up. If there was contact then the valve probably bent and it could have messed up the piston and the valve guide too.

lfhoward said:

I have a diagnosis from the shop.

The #5 cylinder has 0 compression. They say the exhaust valve spring is broken.



Who here has any experience replacing valve springs?

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I've only done it on flat fours. The Only tricky part is how badly the spring itself broke. If part of it made it through the valve...or dinged the seat and piston as others said.

lfhoward said:

I have a diagnosis from the shop.

The #5 cylinder has 0 compression. They say the exhaust valve spring is broken.



Who here has any experience replacing valve springs?

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before you get nuts, HOW did they determine the spring is broken?
bore scope in the cylinder?
did they pull the valve cover off to inspect?