SpeedyRu08

2005 LGT ej255 is burning oil like no one's business, particularly under boost. I started diagnosis with a compression test and the results were:

Cyl 1: 90

Cyl 2: 60

Cyl 3: 80

Cyl 4: 45

I did the test with the engine completely cold (car was sitting outside in 40⁰ weather) and throttle closed so I was expecting the numbers to be a bit lower than usual but not this low.

The engine runs pretty damn good and doesn't even have a check engine light.

It was rebuilt in 2013, it has a BNR 16g turbo and Cobb catless downpipe. Any thoughts? I plan on doing a leak down test tomorrow.

I have a misfire on 3 cylinders so I'm trying to test the wiring on the injectors and coil packs. I couldn't find anything online for an 08 so if anyone has anything I would appreciate it big time.

1 new uppipe and an oxygen sensor later, we have misfires on cylinders 1,3, & 4 actually showing up on the scanner. The check engine light only flashes intermittently but the car runs like shit constantly. I'll try checking the coils and injectors

It's on OEM pipe. After looking at it closely somehow it snapped so I'm gonna replace it with another used one I have and see what all that fixes...

So I just found that the up pipe is in 2 pieces. The upper piece that bolts to the turbo is still attached but I was able to wiggle out the lower part that mounts to the exhaust manifold. I can't imagine this is normal. Can anyone tell me if this pipe is supposed to be welded or something and be one piece?

I would fix all the problems before trying to diagnose a bad ECM. Exhaust leaks can definitely cause an O2 code.

I'm just going to replace all the gaskets on the side where the exhaust leak is and see where that leaves me. I did a smoke test by putting the smoke machine hose in the tail pipe and plugging the tailpipes and all the smoke was coming from the turbo area.

Are you sure the timing is spot on? My preferred method is to count the number of teeth between pulleys as per FSM.

 

I'm almost certain it is. I tried reusing the old belt because it only had like 20k miles on it but the marks didn't line up at all so I got a new belt and the pulleys I needed. The left (driver side) intake cam gear was about a half a tooth off but I've seen that on several other DOHC timing belt jobs I've done (YouTube videos too). Everything else was spot on.

I got this 08 LGT 122k miles, with cross-threaded spark plug threads (previous owner was trying to fix a misfire), I retapped the threads & put in a Helicoil. Also just did a timing belt job on it while putting the head back on. I got it running again and on the first start up, this thing runs like dog sh*t. The only codes it's showing is for the front o2 sensor.

 

It ran pretty rough before I fixed the spark plug and had misfire codes for all 4 cylinders, and when I took the timing cover off it looked like the tensioner plunger failed and may have cause the engine to jump time (timing marks were off about a tooth).

There's also a massive exhaust leak coming from around/under the turbo area that I haven't been able to fully track down.

 

Could this thing have a bad PCM and what's the best way to determine that? Or what would be the ideal tests to run and things to check first? All the plugs and coils LOOKED new. And could the exhaust leak make it run so rough? Any input is appreciated