Novak Conversions Jeep Wrangler TJ engine mounts

Aggressively Rough Idle / Driving

Ol' Bessie's Keeper

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Story time!

I was on the highway headed home a couple weeks ago at night and noticed a power loss, only being able to get her up to 55mph when before, I was coasting at 75mph. I look in my mirror as a car with crazy bright neon lights comes up on me and I see a TON of smoke coming from me; come to find out when I get home that there's oil everywhere underneath. Surely not a coincidence, but when I get home, she just sounds horrible, struggling, super rough driving and idle. Died a couple times while a mile away from home, but we made it.

I have a couple videos showing just the idle, plus a bit of driving in reverse, and also unplugging different injectors to see a change (or not) in how she was idling. Just looking for the next step forward on what should be tested or if anyone flat out can tell what's up, to hear the input. There's also a piercing sound coming from the block that is either piston slap or something else? Broke open the valve cover and everything seems to be fine up top.

Is it better to test rocker arms, springs, etc. if set at TDC? Everything seemed fine.

Changed the oil, and not much was in there. I'm assuming the oil pan gasket blew somewhere and that's why the exhaust was covered.

Only codes I have are p0201 - p0204 because I pulled all the injectors to see how she would run otherwise with negligent change besides #1. Pulled the rail and all o-rings look fine, no cracks on injectors, they seem fine.

Anything I can do before throwing money at parts?
Idling: https://drive.google.com/file/d/1KM_3D2E8qpiDSyKx4yx-X16cnrFcMFAz/view?usp=sharing
Driving in reverse: https://drive.google.com/file/d/1xO2ml8xbt_pygTWUanQKBvattD65r6RW/view?usp=drive_link
Pulling Injectors: https://drive.google.com/file/d/1ggrGTejrSVVeYmh9jkMSB_trho8JnwpV/view?usp=sharing

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Compression and leak down test for one. Then actual oil pressure... remove the sensor and screw in a gauge. if the oil pan is coming off it's easy to pull a crank bearing and look at the condition and note the size. Might want to do a rear main and new Melling oil pump.

-Mac
 
You sure there aren't any new inspection ports in the side of that block? That's a ton of oil where it aught not be.

Trace the source of the leak? ATF from radiator?
Compression
Leak down
Drain oil and check for coolant
Boroscope into the cylinders
Drop oil pan and inspect botton end.
 
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You sure there aren't any new inspection ports in the side of that block? That's a ton of oil where it aught not be.

Trace the source of the leak? ATF from radiator?
Compression
Leak down
Drain oil and check for coolant
Boroscope into the cylinders
Drop oil pan and inspect botton end.

Drained the oil and see a faint trace of contamination, but normal amounts of wear and tear "metal shards" in the oil. I've had a blown head before and she didn't quite act this way, but to be fair, the blown head allowed exhaust into the coolant, not coolant into the oil. If it is blown, is that enough to make her run aggro like that?

Doing a compression test later tonight. The oil pan gasket must have blown, as the head was not leaking oil and the oil filter was still on nice and tight.
Leak down will come after compression testing. Guess I'll snag a boroscope as well to check out the cylinders. Same with oil pressure gauge as @macleanflood noted.
 
Drained the oil and see a faint trace of contamination, but normal amounts of wear and tear "metal shards" in the oil. I've had a blown head before and she didn't quite act this way, but to be fair, the blown head allowed exhaust into the coolant, not coolant into the oil. If it is blown, is that enough to make her run aggro like that?

Doing a compression test later tonight. The oil pan gasket must have blown, as the head was not leaking oil and the oil filter was still on nice and tight.
Leak down will come after compression testing. Guess I'll snag a boroscope as well to check out the cylinders. Same with oil pressure gauge as @macleanflood noted.

Welp, one of these things is not like the other.. :ROFLMAO:

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Take the valve cover off and see what the rockers and push rods are doing.

-Mac

Well I had taken the valve cover off yesterday to see if there was any shrapnel on top from any of the pushrods or rocker arms, but they all seemed tight/straight. Nothing bent or out of the ordinary, and plenty of oil on top. I'll have to rip it off tomorrow and start her up in the AM to check out #3.
 
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A bent valve wouldn't dump oil all over the engine bay, would it?

Wheres the hole in the block
 
I don't think ol Bessie is OK. None of them look good. Those are REALLY sooty and 2-3-4 look very oily. It could be a cracked piston blowing down into the crankcase and then sending oil through the breather by the bucketful.

You are absolutely correct. Here is a lovely picture of the top of piston #3. :ROFLMAO: I really did not luck out on this whole scenario.
A bent valve wouldn't dump oil all over the engine bay, would it?

Wheres the hole in the block

Lol, I mean I'm right there with you. Busted piston, but don't see a hole in the block...yet. I'll be ripping her apart to find out though.
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Good time for a 4.0l or v8 swap!

I probably wouldn't do a 4.0 swap into a 4-cyl as it requires the 4.0L PCM too and alot of the other work of any other swap. If you want to keep using the gauges it needs to be from a similar year.

Just go to something better of you're going to go through the trouble. Not meaning to shit on the 4.0, but if I had to replace a motor I'd be looking at something alot more modern and capable of alot more power.

You are absolutely correct. Here is a lovely picture of the top of piston #3. :ROFLMAO: I really did not luck out on this whole scenario.
I don't like being right in this case. Sorry Bessie. It's glue factory time.
 
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Here is the beautiful piston #3! Cylinder is scored a little bit but doesn't seem aggressively bad. Here's the head too. The valves actually look to be sealed properly. All though there is a knick in one of them if you zoom in and look closely. Obviously covered in oil because...well...yeah.

I still haven't found a hole in the block anywhere yet; gonna keep removing stuff and take a thorough look. Bunch of oil in the intake though, as to be expected. I threw in the last picture because the third head bolt on the right side was rusted over? Not sure how that would happen.
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Unlikely to have a hole in the block with this failure, but what happened! It doesn't look like a valve is bent after hitting the cylinder and it's not showing signs of melting from running dangerously lean.
 
Does that bolt go into a coolant passage? If so it takes thread sealant and a lower torque value

No. Mid-headbolt. Not the one that's in the front position. No idea why there's rust.

Unlikely to have a hole in the block with this failure, but what happened! It doesn't look like a valve is bent after hitting the cylinder and it's not showing signs of melting from running dangerously lean.

Yeah haven't found a hole. Looked up from the inside with the pan off and didn't see anything. Doesn't explain the massive amount of oil that spewed out all over the undercarriage though.

The rods all seemed to have the same play on the crank; minimal. The piston could have just failed for whatever reason. Again, I was cruising on the highway when it happened.

Regardless, a ton of oil underneath when it happened. Not sure what could have happened. Oil pan gasket seemed intact. Unless THAT MUCH OIL was able to gush through cylinder #3 and blow back into the whole system and shoot out somewhere? Just doesn't make sense.

Thoughts?

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Novak Conversions Jeep Wrangler TJ engine mounts