Compression test shows cylinder 4 at 80psi while the other three are at 145. Thank you GM.
P0304 Code After Valve Cover Replacement
I’ve got a 2012 Eco with 60k miles that up till recently has been a solid and reliable car. Mileage is consistently in the high 30’s. Couple weeks ago, I noticed power loss on the highway and had to downshift to keep the RPM’s up as this was the only way to accelerate. At low RPM’s, the car would stutter and I’d have to get into 3K+ RPMs to move around. It felt as if the turbo died. No CEL.
The next day, I noticed a puddle of oil under the car and lots of smoke coming out of exhaust when first started. I found that oil was leaking from the throttle body and drove to the dealer for diagnostic and repair. The dealer confirmed a PCV problem and replaced the valve cover, cam seals, and water pump.
The oil leak was still there over the next couple of days of driving so I took it back but now the CEL was on as well showing P0304. Plugs and coil pack were replaced but the code keeps coming back. Dealer claimed that leaking oil was residual and did some additional cleaning.
The oil leak has stopped. I cleared the code but it comes back in ~50 miles with the Stabilitrac light. The Stabilitrac light comes and goes but the CEL is now constantly on. The CEL flashes at times. My next steps involve taking the throttle body off and cleaning it thoroughly. Any other ideas? The car drives fine and besides the CEL light, I believe the MPG’s have gone down but I won’t be able to confirm until a few more days.
The next day, I noticed a puddle of oil under the car and lots of smoke coming out of exhaust when first started. I found that oil was leaking from the throttle body and drove to the dealer for diagnostic and repair. The dealer confirmed a PCV problem and replaced the valve cover, cam seals, and water pump.
The oil leak was still there over the next couple of days of driving so I took it back but now the CEL was on as well showing P0304. Plugs and coil pack were replaced but the code keeps coming back. Dealer claimed that leaking oil was residual and did some additional cleaning.
The oil leak has stopped. I cleared the code but it comes back in ~50 miles with the Stabilitrac light. The Stabilitrac light comes and goes but the CEL is now constantly on. The CEL flashes at times. My next steps involve taking the throttle body off and cleaning it thoroughly. Any other ideas? The car drives fine and besides the CEL light, I believe the MPG’s have gone down but I won’t be able to confirm until a few more days.
1 - 7 of 7 Posts
Likely failed piston.....on GM's dime.....5yr 100k powertrain.
Things happen.....that's why there is a warranty
Rob
Things happen.....that's why there is a warranty
Rob
There is no oil consumption as far as I can tell. Because this happened in conjunction with a PCV blow-up where oil was hitting the intake in significant quantity, could it be a leaky exhaust valve?
If failed piston, are all four replaced to ensure equal compression?
It's going back in tomorrow and I sure hope I don't get a runaround on the warranty. I'm wondering if this is an indicator of future major engine problems. If this happened a few months later, I'd be out a big chunk of change for something that really shouldn't be happening to a 60k engine.
If failed piston, are all four replaced to ensure equal compression?
It's going back in tomorrow and I sure hope I don't get a runaround on the warranty. I'm wondering if this is an indicator of future major engine problems. If this happened a few months later, I'd be out a big chunk of change for something that really shouldn't be happening to a 60k engine.
Cracked piston ring. My build was 9/11. Austrian engine?
Just a off the wall guess but I remember when my cruze was having the stabillalink issue it was due to the coolant temp sensors and was a safety mechanism in the car because of it. I believe there are 2, 1 right below the water outlet on the engine itself, and another on the intercooler frontpassenger side. I believe they were pretty cheap and it fixed all my problems. Hope it helps, dealing with a stuttering when above 3500 rpms due to a bad fuel injector I believe. Already replaced the intake manifold/3 valve covers/ThrottleBody/WaterOutlet/coolant sensors.There is no oil consumption as far as I can tell. Because this happened in conjunction with a PCV blow-up where oil was hitting the intake in significant quantity, could it be a leaky exhaust valve?
If failed piston, are all four replaced to ensure equal compression?
It's going back in tomorrow and I sure hope I don't get a runaround on the warranty. I'm wondering if this is an indicator of future major engine problems. If this happened a few months later, I'd be out a big chunk of change for something that really shouldn't be happening to a 60k engine.
OP this thread is 5 years old 😃. diagnosis was a cracked piston ringJust a off the wall guess but I remember when my cruze was having the stabillalink issue it was due to the coolant temp sensors and was a safety mechanism in the car because of it. I believe there are 2, 1 right below the water outlet on the engine itself, and another on the intercooler frontpassenger side. I believe they were pretty cheap and it fixed all my problems. Hope it helps, dealing with a stuttering when above 3500 rpms due to a bad fuel injector I believe. Already replaced the intake manifold/3 valve covers/ThrottleBody/WaterOutlet/coolant sensors.
1 - 7 of 7 Posts
- This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Chevrolet Cruze Forums
CruzeTalk.com forum, news, discussions and the best community for owners to discuss all things related to the Chevy Cruze.
Full Forum Listing
Top Contributors this Month
View All
Cruze CTRL
75 Replies
Cruzing12
54 Replies
Valpo Cruze
50 Replies
Recommended Communities
