2008 Saturn Aura - Stalling

[Fishinguy40]

Car is a 2008 Saturn Aura, 2.4L, 104,000 miles.

 

It's my daughter's car.  She's complained off and on over the last 18  months that the car will intermittently run rough and/or stall.  Never throws a code.  I've gone through every wire harness that I can find both inside the car and under the hood.  No issues found.  I've also gone through every ground connection that I could find and checked connectors, putting dielectric grease on all of them to ensure no fretting corrosion.  The problem has been very intermittent.  Sometime not happening for several months.  But seems to be reoccurring more now.  She called a couple weeks ago and said that the car stalled at the parking ramp at MOA after she hit a pothole.

I've been driving the car for the last two weeks.  And here are the symptoms that have occurred while I've been driving it.

First week nothing.  Drove fine.  I gave her the car back and next day she calls and says the check engine light is on.  I pull the code.  I think it was PO014.  I did clear it so I hope I have the code right but when I looked it up it was for Camshaft Position Actuator Solenoid Valve.  Auto stores called them Variable Valve Timing Solenoids.  So I replaced both actuators, as it is a dual overhead cam.  Both were clogged with fine metal shavings or powder.  The media was metallic.  Checked with a magnet.  Media was very fine.  No sharp edges.  Changed the oil.  Checked both actuators again after a day of driving and both were clean.

Car ran fine for a few more days.  Then one day when I was sitting at a stop light I could feel the car surging.  Looked at the rpm gauge and it was bouncing up and down slightly.  Car accelerated fine when the light turned green.  This happened again a day or two later.

On Wednesday I pull into the garage at home after work and the car just quits as I'm coasting into the garage.  It was immediate, almost as if I turned the ignition off.  Engine wasn't running rough.  Put it into neutral and she started right back up fine.  No problems.

Yesterday, I get thinking.  Daughter said she hit a pothole before it stalled.  It stalled on me when I pulled into my garage.  I do need a new driveway.  My apron is sinking in front of the garage so there is quite a lip when pulling into the garage.  Almost like a speed bump...LOL.  So when I get home from work I pull into the garage a little faster than normal so that I hit the bump hard.  Sure enough, car starts running really rough.  I put it into neutral and park and she still runs rough.  Almost on the verge of stalling.  I could hear a loud and distinctive clanking from under the hood.  I kept it running and popped open the hood and the sound was coming from under the valve cover.  Shut car off.  Started it back up.  Ran fine and smooth.

Met my daughter at Gander last night in Lakeville.  We spent an hour at the indoor range.  The car stalled on me as I was pulling into a parking spot.  Again it just died.  Engine wasn't running rough.  I think I hit a pothole in the lot before turning into the spot.  After we were done, I went home and pulled into the garage hard again.  Sure enough, car ran rough.  Though I didn't notice the loud clanking this time.  The car stalled again this morning as I pulled into a parking spot at work.

 

The car seems to just stall immediately or run rough after decelerating/stopping.

No codes except for the one mentioned above.  The symptoms seem to vary some but the only consistencies seem to be car acts up when decelerating (sitting at a stop light, pulling into garage or parking spot) and possibly mechanical agitation, such as when hitting a pothole.

 

Ideas?

 

 

 

[jmd1]

how many miles and has it had a fuel pump put in it ever?  Sounds to me it might have a fuel issue.  Just thinking thru what you mentioned. Can you hear the pump whining?  Had a dodge truck that as soon as i could hear the pump noise it would need a new one.  All done under warranty.  Good luck, i hate gremlins.  

[Fishinguy40]

I was thinking possible fuel pump.  As when she was running rough the other day it seemed like she was starving for fuel and the knocking I heard may have been detonation due to running too lean.   It's original pump as far as I know.  

This weekend I'm going to through a gauge on the fuel rail and see if I can get it to act up again.  I don't want to drop the gas tank if I don't have to.

[Datman7890]

The ignition control modules can do some weird things on them engines, Could be related to the problem. When it stalls does it start right back up? The noise you were hearing could be from misfires and creating the timing chain to slap. Common for them to stretch out also.

[Fishinguy40]

Car starts right back up and runs fine.

[Fishinguy40]

After taking the car to Airjer, it appears to be a faulty camshaft actuator/ phaser.

[Fishinguy40]

An update on what happened.

 

Airjer suspected an issue with cam phaser and possibly oil delivery to the top end of the engine because of valve noise.  So I decide to replace the cam phasers.  When I attempted to rotate the engine by hand, via the camshafts, the timing chain jumped on the cam sprocket.  Great!

 

So I purchased a new timing chain and chain tensioner and began the disassembly.  When I got the front cover/timing cover off I found something that I was not expecting.  The stationary timing chain guide was broken.  Below is a picture of the pieces of the chain guide.

The top bolt that held the chain guard in place was gone.  The bottom bolt was sheared.  Drilling and tapping that was fun.  Only 5 inches of space because of the frame.  I had to purchase a right angle attachment for my cordless drill but it did work.

 

I also discovered where the metal shavings came from that I described in the original post.  The timing chain was rubbing on the housing as evidenced by the marks that it left.

 

You can also see that the timing chain was stretched when compared to a new chain.

 

 

So I ended up replacing both cam phasers, timing chain, chain tensioner, guides, serpentine belt (since it was off for disassembly) and I pulled the oil pan to recover the missing/broken parts.  Didn't see anything in the oil pan and no rattling.  So I pulled the baffle and the oil pump suction line.  The missing bolt, sheared bolt head and several pieces of the chain guide were all stuck up inside the suction line strainer.  I didn't get any pictures of that because at this point my hands were quite oily and I didn't want to handle my phone.

 

Got it all back together put new oil and oil filter in.  Drove it to work yesterday and noticed when the engine gets hot and you come to a stop you can barely feel what feels like a slight miss as the car idles.  After work drove home and changed oil again.  There was debris in the brand new oil filter after driving approximately 40 miles round trip to and from work.  Not surprising after all the disassembly and cleaning that I did.  Drove it to work this morning and the slight miss at idle is better but still slightly noticeable.  I suspect that with the damage that I found there is debris moving through the oil system.  Also, varnish that may have been loosened with the disassembly and reassembly.  This may affect the cam phasers, VVT solenoids or a sticky valve.  I plan to run some sea foam through the oil and hopefully clean things up a bit better.  I also plan to pull the VVT solenoids to clean and inspect.

Hopefully this will be the final fix because it sure seems like something is sticking.  You can feel the slight miss, watch the rpm gauge ever so slightly fluctuate and then it just stops.

 

If I discover anything else I will update the post.

Edited February 18, 2016 by Fishinguy40