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Discussion Starter #1
I’ve got all of these codes popping up, P0011 P0013 and P0016 and I can’t figure this out.

I replaced the Exhaust actuator solenoid but no change,

I can’t get the crank sensor to change it because they made it resiculoisly difficult to get to,

I tested resistance on cam position sensor and got 1400 ohms but I can’t find out if that’s in spec or not,

Then I took off valve cover and inspected timing chain and it’s slightly loose but I don’t think it could jump gears.

My cobalt is making a slight tapping or knocking noise and when I leave it run for about 5 minutes it starts screeching like a metal to metal noise and sounds horrible when I shut it off.

Any thoughts?
 

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To have an intake and exhaust cam code at the same time with a camshaft correlation almost sounds like a camshaft sensor, but maybe your timing chain has stretched to the point where your cam actuators can't fall in the range anymore or maybe it even jumped a cog. This would cause loss of power, knocking and timing chain shouldn't be loose if your tensioner is good. Do you have first or second design?

 

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Discussion Starter #3 (Edited)
I believe I have the first design by the looks of the bolt end. I haven’t taken it out yet. Would it be possible to only need the tensioner? The chain and guides look like they’re in good shape.

*update
I did an oil change and changed the filter(it was very sucked in and bend crooked. Not my doing this is a new purchase)

Now I cleared the codes and the only one that came back was P0014 (Exhaust Camshaft Position Timing Over Advanved).

Keep in mind I didn’t let it run long though because the sound is very, very bad and I don’t want to blow the head and smash valves. So maybe more would have came back I don’t know. I only ran it 3-4 minutes.

---------- Post added at 02:29 PM ---------- Previous post was at 01:25 PM ----------

Something I thought of, maybe the other codes really are gone. They were “Permanent” codes so they would not go away unless the issue that set the codes did. So the only code I have now is P0014.

Honestly everything is normal besides the stutter and hesitation along with the horrifying noise. It fires up on a instantly and I even cranked it by hand to prove that it cranks very easily and smoothly.
 

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But noise is never good, what type oil did you put in? And maybe you're right if the exhaust actuator is stuck wide open it could be the cause of all...
 

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Discussion Starter #6 (Edited)
Well I did replace that. Is it possible to not get it in all the way or install it wrong somehow? (I’m new to these VVT motors)

*I put in a typical 5w-30. The oil that was in it was horrible. Thick and pure black.

---------- Post added at 07:18 PM ---------- Previous post was at 05:56 PM ----------

Is there anything else that can cause the P0014 code? If it’s directly related to the Exhaust Actuator Solenoid then I suppose I’ll take the new one back out and see what’s going on. Maybe I got something down in the hole when I was changing it? I did have to drill out the old one so it’s possible...

---------- Post added at 09:03 PM ---------- Previous post was at 07:18 PM ----------

*****After non stop research, I think I’ve found the culprit. The harmonic balancer. Could this cause the timing to be off slightly causing the p0014 code? This would explain the horrific sound, the belt popped off once, everything. I’ll be checking it out in the morning!
 

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Discussion Starter #7
Bump

---------- Post added at 06:37 AM ---------- Previous post was at 05:27 AM ----------

Is There A way to check timing without starting the engine?
 

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Yes, but you have to take the valve cover off.

 

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Discussion Starter #9
Timing looks good to me. That picture is when #1 cylinder is TDC correct?

I checked the harmonic balancer by firing it up for a 30 seconds and it does wiggle/wobble a bit but I can’t tell if that’s the culprit.

I took the new Exhaust acuator spolenoid out and checked for debris. There was a little, some small metal pieces ( probably from me drilling it the old one..) I cleaned it up and cleaned out the port in the head. Now I’m waiting for battery to charge to try and start again.

The screeching noise is getting worse every time I start it. Now it’s almost sounding like it’s backfiring inside the engine....
 

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Discussion Starter #10
I opened up that valve cover again to look at the timing chain. It very hard to make out the colored links but I think I see them. 2 red and one black? Would the black be for the crank and the two reds for the cam shafts? If so, something crazy is going on.

As I rotate the crank clockwise, each time the red marks pass the Cam shafts, they aren’t near the marks and their location to the marks on the gears always changes. Every lap around they change. One time the red mark was 2 links away from the mark on the intake gear, and the next time it was 7 links away. How is this possible? It feels tight for the most part unless I really pull on it
 

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Discussion Starter #11
Anyone have any ideas? I’m lost. The sound it’s making doesn’t correspond to anything to do with the camshafts IMO, it is pure screeching metal to metal, but the codes only point to crankshaft and camshaft timing correlation... I don’t get it. The chain seems tight until I turn the crank counter clockwise then there is some slack. But as long as the engine never does a 360 and starts running backwards there wouldn’t be slack lol.

Another thing, when I’m cranking the engine by hand, it doesn’t make any sort of screeching or a single tap. I know pressure from combustion changes a lot but you’d think the screeching would still happen when I crank manually..
 

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Never turn an ecotec backwards more than 15 degrees. Just not designed to turn that way. You could always pull the spark plugs to make it easier to turn the crank. At one point 2 of those links should match up perfectly with those marks on the cam gears, if not you jumped a cog and may have valve damage.
 

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Discussion Starter #13
I really appreciate all the help! I’ll check in the morning to see if I can get the marks to line up. I heard it can take 25 revolutions...

I have one more question for you. When I was cranking by hand today, I noticed the intake cam shaft moves exactly when the intake gear moves and without any kind of “play or slack”, but the Exhaust gear freely floats even after I stop cranking and the Exhaust gear isn’t even moving. It floats probably 10 degrees on its own (Maybe more it’s hard to tell).

Does this indicate anything?
 

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There shouldn't be any play to my recollection.
 

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Discussion Starter #15
Is There A part on the cam from the sprocket back, that could allow for play? (Sorry again for all these questions, I know very little about VVT and VVT cams).

Maybe I should go get a local used Exhaust cam and swap out?
 

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Discussion Starter #16
An update:

I took out the chain tensioner and it turns out to be the second design in the picture you had sent me originally. How can I check to see if it’s bad? Also, I finally got the cam marks to match up on the timing chain, so it appears to be timed right.
 

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Here is how to reset your tensioner.

 
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