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Hi forums members, I am new here and to the Cobalt platform.
I just purchased a 2006 Cobalt SS/SC with essentially a ZZP Stage 2 kit with 2.9" pulley.
Oil is spewing from all corners of the valve cover gasket and the oil fill cap. I am also seeing blue smoke (likely oil) from the tail pipe.
The previous owner said that was not happening before I bought the car. I have no reason not to believe him as I don't see any evidence of previous oil issues in the engine bay.
He recently put in a new purge valve, and a catch can system and maybe a new PCV(?).
I don't know these platforms well enough and searches have pulled up nothing for me at this point. I feel like something is probably blocked in the PCV system but I'm not 100% sure on that. So I turn to the collective for a little help.
Is the catch can VTA or is it plumbed into the intake? If it's VTA, that's your problem. One way or another, the PCV systems on these cars are undersized from the factory, so fixing it is a good idea - requires a little customization though (I might be making a couple modified valve covers for this in the coming month or so. I have too many damn projects).
I see some issues, but not related to what you came here about.
Have you pulled your plugs and looked at them? How's the car been running? I would start the car, pull the PCV line off of the back of the valve cover, and make sure you're getting suction/vacuum pulled through the hose.
Honestly, I fear the worst here. If it's SPRAYING oil out like that... you likely have a serious crankcase pressurization problem. I would advise running a compression test at a minimum and then probably a leak down.
Thanks USMCFieldMP for all the help!
I'm going to try and get a hold of compression test and leak down test equipment.
In the mean time I am wondering if the PCV inside the intake manifold has went the way of the ghost? I found an old thread and everyone said contact Tom@CED which I have done. Is he the only source for this part?
Compression test at a minimum; that'll likely tell you the most. I'm starting to wonder if maybe the valve stem seals are just absolutely wasted and that's your issue.
If the check valve in the intake manifold went bad, then yes, that could be your issue. If you have access to pressurized air, you should be able to test that fairly easily. I'd make put a PVC cap in a silicone joint and slip that on the throttle body, then pull the vacuum hose off of the top port of the intake manifold, pressurize. You're essentially doing a boost leak test on the intake manifold.
Tom@CED just has good prices and has always supported this forum really well; especially in the early days of the car. You can get it anywhere, but a lot of us go through him for OEM parts.
Compression test at a minimum; that'll likely tell you the most. I'm starting to wonder if maybe the valve stem seals are just absolutely wasted and that's your issue.
If the check valve in the intake manifold went bad, then yes, that could be your issue. If you have access to pressurized air, you should be able to test that fairly easily. I'd make put a PVC cap in a silicone joint and slip that on the throttle body, then pull the vacuum hose off of the top port of the intake manifold, pressurize. You're essentially doing a boost leak test on the intake manifold.
Tom@CED just has good prices and has always supported this forum really well; especially in the early days of the car. You can get it anywhere, but a lot of us go through him for OEM parts.
Are you near Fort Worth?
I'll be able to get a hold of it this week for sure and hopefully test this weekend on that end.
I will also look into doing that type of test, I do have compressed air.
Ahh ok, I just couldn't even find a part # or anything using GM parts sites so I wasn't sure even where to start.
I am in Elgin, TX (about 20 minutes east of Austin) so I am not super close to FTW.
I see some issues, but not related to what you came here about.
What other issues do you notice?
One thing I see if the oil dipstick is turned into the wrong position/angle. I plan to address this with I do the oil pan gasket.
The hose doesn't look tight on the quick disconnect for the brake booster connection (just left of the throttle body, on the S/C)... but that could just be optics.
It does look like there's a good number of newer sensors though and that all of the vacuum lines were recently replaced.
I pulled the supercharger and intake manifold. As I was certain it was a bad PCV.
PCV is new, and seems to be flowing 1-way.
Pics.
The gasket (i'm guessing an OTTP) doesn't seem to line up quite right. I know there was an updated gasket from a TSB but can't find what changed.
OTTP and ZZP just supply OEM intake gaskets - they don't have their own versions.
The entire engine is out of a Saab. There's a few differences here and there, but the LSJ is essentially a Saab B207 engine. GM owned Saab, in case you didn't know.
Ordering new gaskets and some random bolts that are missing from CED.
When back together I'll check the compression and leak down test
Unsure of oil level. It isn't on a level surface at the moment. Going by the oil found in the vent tube lines and the pool I found in the air intake tube, things are moving freely through that system.
Yeah I knew the engines were essentially the same, just funny to see the SAAB stamp.
If you get a bubble of air locked in a line between two pockets of fluid it can effectively prevent flow even when applying a lot of pressure or vacuum. I'd clean the lines out very well and make sure the catch can isn't filling up after reinstalling everything. I'm just throwing a guess out, but if the catch can filled up it would cause a lockup on the pcv which could cause a build in pressure.
Now I agree a compression and leak down will be the best thing to do, be sure to remove the oil cap during the leak down to confirm if its the valve seals or do one better and remove the valve cover completely.
OOF! I'm suspicious... only because EVERY cylinder is so terrible.
99% of the time, your crank and rods will be fine. Most likely you only need new pistons/rings and probably a block. I have an LAF block in my garage that can be used - you'll have to order ZZP's special 88mm LSJ pistons and the crank sensor spacer. Then you'll have a 2.1L engine.
But on second though... with every cylinder being so terrible, I'm wondering if your issue is the cylinder head and valve related (i.e. the engine was mistimed or jumped timing). You might try putting a teaspoon of oil in each cylinder right before compression checking it. If the numbers stay relatively the same, then the valves are your issue. That'll at least help narrow down where your problems lies.
EDIT: nevermind, I forgot you were having the high crankcase pressure issue... I doubt your valves are the problem then. Or at least, not your only problem.
Last edited by USMCFieldMP; Sep 23, 2021 at 12:43 PM.
Having a heck of a time trying to source a rebuilt/refreshed LSJ (or even a junkyard LSJ).
Would a SAAB 9-3 B207R short block work? It seems those are much more plentiful.
They didn't make a lot of SS's to start with, and people have not been kind to them, so there are even less of them on the road now... so yeah, engines and transmissions can be hard to come by.
The B207R works. You still need the LSJ head and there are a handful of other modifications to be made, as well. I don't know all of them off the top of my head though, but the info is probably on here somewhere (plugging the turbo oil drain is definitely one of them though).
I now have an engine on the way. 106k miles, I've seen video of it running and compression test results.
My question now is; What all should be replace on the "new" engine before putting it into the car?
Front/Rear main seals - yes
Oil pan "gasket" - yes
Valve cover gasket - yes
Exhaust manifold gasket - yes
Intake manifold gasket - yes
Thermostat and gasket - yes
Should I do a full timing chain service?
- Crank bolt
- Front cover gasket
- water pump
- both timing chain kits
- chain tensioner
To be honest, I haven't heard of front or rear main seals being issues on these cars, but they're also not all that expensive or hard to replace. Same for the oil pan RTV gasket... eh, if there aren't signs of it leaking, I wouldn't mess with it.
Everything else, yes.
A full timing service would be at the top of my list.
EDIT: looking back at your pictures, when you put new spark plugs in, use NGK BKR7E's. The BKR6E's that were in it are the factory recommended plugs for a stock engine... once an LSJ is tuned and pullied down, you need to move to the BKR7E. I recommend the basic copper BKR7E over the IX's. I still use those with my big turbo setup.
To be honest, I haven't heard of front or rear main seals being issues on these cars, but they're also not all that expensive or hard to replace. Same for the oil pan RTV gasket... eh, if there aren't signs of it leaking, I wouldn't mess with it.
Everything else, yes.
A full timing service would be at the top of my list.
EDIT: looking back at your pictures, when you put new spark plugs in, use NGK BKR7E's. The BKR6E's that were in it are the factory recommended plugs for a stock engine... once an LSJ is tuned and pullied down, you need to move to the BKR7E. I recommend the basic copper BKR7E over the IX's. I still use those with my big turbo setup.
BTW: Thank you so much @USMCFieldMP I really appreciate all the help you've provided. This has been a pretty shitty ordeal and glad someone was able to talk me though this process a bit.
That's the plug. I have like 3 or 4 packs of them in my tool box.
And you're welcome. Buying a car and almost instantly finding out the engine is trash... not fun.
Tear that old engine down and figure out what is wrong with it and what is salvageable. If the bores are good, you could fix, reassemble, and sell to recoup some of the money spent on the new engine. I have a decent amount of spare parts, if need be, although I have started to thin out my collection.
