2010 Camaro 2SS L99 No Compression Left Bank - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

Pablo Azcobar · 02-01-2021, 04:01 AM

hi sirs! I have a 2010 Camaro 2SS L99 with about 10000miles on it.

A few months ago I started it and while idling really well, it backfired once, and then kept misfiring after, after some time it felt like it was running on only 4 cylinders, and a few minutes later, showed the LOW OIL PRESSURE warning and it shut off. I scanned it and it had misfire codes on cyl 1, 3, 5, 7.

I also noticed the left exhaust blowing out metal debris, more like sand so I removed the cats, and yes it was the left side cats.

I also did a compression test with throttle full open, and 1, 3, and 5 showed 30psi, while 7 showed 90. The right bank shows 220 more or less on all 2, 4, 6, 8.

So, I removed the left head, as I suspected some debris stuck on the valve seats, and there was non. Did a valve leak test with gasoline and no leaks.

I reassembled it, then did a compression check and it was the same 30psi. Also started it and it was still running on 4 cylinders only, and then gave me the LOW OIL PRESSURE warning at idle. Giving it a bit of gas would bring oil pressure up to about 30 to 40 psi.

I suspect the lifters crack the valves open a bit. I dont understand how the cylinder shut off works on the L99.

Not much help out here in the Philippines.

Really need help on this one. Thanks!

02-01-2021, 04:01 AM	#1
Pablo Azcobar Drives: 2010 Camaro 2SS, 2014 Jeep JK Join Date: Dec 2020 Location: Philippines Posts: 1	2010 Camaro 2SS L99 No Compression Left Bank hi sirs! I have a 2010 Camaro 2SS L99 with about 10000miles on it. A few months ago I started it and while idling really well, it backfired once, and then kept misfiring after, after some time it felt like it was running on only 4 cylinders, and a few minutes later, showed the LOW OIL PRESSURE warning and it shut off. I scanned it and it had misfire codes on cyl 1, 3, 5, 7. I also noticed the left exhaust blowing out metal debris, more like sand so I removed the cats, and yes it was the left side cats. I also did a compression test with throttle full open, and 1, 3, and 5 showed 30psi, while 7 showed 90. The right bank shows 220 more or less on all 2, 4, 6, 8. So, I removed the left head, as I suspected some debris stuck on the valve seats, and there was non. Did a valve leak test with gasoline and no leaks. I reassembled it, then did a compression check and it was the same 30psi. Also started it and it was still running on 4 cylinders only, and then gave me the LOW OIL PRESSURE warning at idle. Giving it a bit of gas would bring oil pressure up to about 30 to 40 psi. I suspect the lifters crack the valves open a bit. I dont understand how the cylinder shut off works on the L99. Not much help out here in the Philippines. Really need help on this one. Thanks!