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Blue Smoke - Identifying Problem

cosunrise

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Hi all- new owner of a 2018 JL with 83K, just bought her as a salvage to do a one ton swap and build.

HUGE amount of blue smoke from tailpipe on cold start... Less as she warms up but still very visible. Oily fluid actually drips from the weep hole on the muffler after a while. Spark plugs are ugly and oily.

Codes are:

P0108 MAP Sensor circuit high
P012D Turbo inlet pressure sensor circuit A high
P2174 Throttle actuator control sudden low air flow
P0123 TPS A circuit high

I'm pretty mechanically capable but zero experience with this engine, so I'd welcome the wisdom of the group here on where to start troubleshooting.

Jeep Wrangler JL Blue Smoke - Identifying Problem 59dc8fba-ebc9-4636-a5a1-6fa949767e95


Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250308_223117664
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Jrocket

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Check the pipe from the turbo to intake and the pcv pipe for excess oil first.
 

azjl#3

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^^^

that and that oil looks like used rear end lube.
 
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cosunrise

cosunrise

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There is oil at both ends of the intercooler from the turbo to the intake. There is also oil in the PCV line.
I'm trying to locate the PCV valve and figure out how to swap that out. Any tips on that?

Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250308_233538502.NIGHT


Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250309_003303448.NIGHT


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Jrocket

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I would remove the other pipe from the turbo to inspect it as well.
 
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cosunrise

cosunrise

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Thanks jrocket, which other pipe on the turbo are you referring to? I removed the one between the throttle body and the turbo- Mopar calls it the Charge Air Cooler Duct. are you referring to something different?
 

Jrocket

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The air filter box to turbo and the other tube from the valve cover, and inspect the turbo probably full of oil as well.
 

grimmjeeper

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Could be a blown head gasket or the rings are shot. Could also be valve seals. Could be multiple things at once. Turbo, PCV, and EGR are easier to check first. But a salvage Jeep on tons may have been abused a bit.
 
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cosunrise

cosunrise

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Thanks- I'll pull the cold air intake and see what that side looks like.

Is there any special compression test procedure for this engine? Specific fuses to pull? Can I use the remote start to crank? Do I manually hold the throttle baffle at wide open? And finally, what's the expected compression range for this engine?

Can't find much online about this engine for some reason. Apologies for all the questions.
 

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cosunrise

cosunrise

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Ok, ran a compression test. Pulled the fuel pump fuse, held the throttle open with a paint stick, and had to hit the start button inside manually because remote start is locked out when the hood is open.

The results were, I think, positive:

Cylinder 1 - 120
Cylinder 2 - 120
Cylinder 3 - 125
Cylinder 4 - 125

Axles are pulled for my one ton swap, so I couldn't warm the engine up quite as much as if I'd been able to drive it. High idle in the driveway for a while but couldn't get her over 88 C and I was losing daylight, so I just went for it.

Also attached are photos of the turbo cold air intake- a little oil coming in from the crankcase ventilation pipe, but the impeller doesn't look overly "wet".

Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250310_011733856_exported_5100


Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250310_011733856_exported_0


Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250310_012250399


Jeep Wrangler JL Blue Smoke - Identifying Problem PXL_20250310_012243354
 

PT's19Rubi

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The compression numbers sound okay for a 10:1 ratio engine. By chance has the jeep been on its side or upside down?

If you find no other reasons for the oil, I would suggest cleaning it up and adding a catch can. Once cleaned up, if it still smokes it probably needs a head job. The compression test checked the rings and sealing of valves in combustion chamber, but not the valve seals.

For remote cranking, try pushing down one or the other or both plunger switches to the right of, and slightly behind the radiator top. They are the Hood Closed Switches (I have the 3.6 and assume switched are in the same place).
 
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cosunrise

cosunrise

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I don't know for sure since I just bought it as a salvage vehicle, but the damage to the aftermarket fenders and wheels suggest it was on its side at some point. I figured there could be oil in the cylinders from that, but thought it would burn off pretty quickly.

Any recommendations on how to clean the boost/crankcase pipes and throttle body? Seafoam/CRC into a vacuum line?

I realize the other possibility is that the turbo could be leaking oil internally and feeding it down the boost pipe to the throttle body, but I'd like to rule out other possibilities before going to turbo replacement.
 

azjl#3

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Looks like it was run with the oil all over engine in dirt or sand.

I'd spray off motor as best you can without getting water down the turbo pipes, check all those turbo valves and such, clean that up (brake cleaner), new oil, what codes you getting?
 

Jrocket

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Lots of brake cleaner and rags. Might be a good idea to remove the intake to clean as much oil out. While that is off you can check the oil separator too.
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