socalHHRguy

Hello, my 2008 LS 2.2L with ~100,000 mostly Socal Freeway miles on it has, unfortunately, developed some REALLY nasty clattering in the valve train. Since this website suggested clogged camshaft followers, I decided to do an oil/filter change myself. I found the oil filter has at least two blown areas on the media and I now suspect that the filters may not have been replaced by the local oilchange mill with each oil change.

Per the advice on this GREAT website, I've done MY own oil/filter change and replaced the blownout filter with a WIX brand. During MY changing process, again per some advice hereon, I added Marvel Mystery Oil until I can afford the AutoRX Sludge removal program.

So far (~30 miles post change) the clattering has not improved at all. The only codes I'm getting are misfires - so question #1 is could that be from a compromised follower?

Second question is - Has anyone done their own Valve Job on one of these Ecotecs yet? Due to budget, there's nowayin**ll I can afford a dealer job, if they want to rape us $350 just to change a thermostat.

I found a HOWTO for pulling the valve cover, but so far no searching has yielded anything about R&R the head for a valve job.

In advance, I thank you all for any advice on this.

Snoopy

Completing a "valve Job" successfully is not something a shade tree mechanic should attempt. So I would say....it really depends on your level of expertise....or at least someone to assist with a great deal of knowledge on multi cam-multi valve engines.

And recognize, because of the design, that ALMOST the entire engine needs to be disassembled.

But frankly, you really need to determine ABSOLUTELY, what is the cause of the problem.

foolmoon_design

a valve job would SUCK! especially since the computer controls it, I would look there first. if this isn't it, then ouch

bk94si

I don't think clattering is a sign of bad valves unless one of them somehow got bent. How did you decide it needed a valve job?

nacademus

You sure its not the exhaust cam sensor and housing clattering... they can sound similar. Did on my Cobalt.

843de

I'd lay money that its not the valves, more than likely the cam followers are gunked up and sticking. Another possibility is the timing chain tensioner being stuck or lazy due to a build of up gunk from the blown filter. Unfortunately the EcoTec engines aren't maybe the most user friendly when it comes to DIY work like your contemplating. How many miles do you suspect the engine might have been operating with unfiltered oil, and how many miles on average do you run between oil changes? All you might be dealing with is an engine that is gummed up inside rather than a valvetrain failure. Even though repair costs are an issue, and they are for everybody, I'd take it to a tech and let them check it over just to get an accurate idea of what's going on before a teardown that might not be needed.

socalHHRguy

OK, THX for the inital thoughts. In order:

SNOOPY: I do appreciate that the dual OH cam design is going to make it messy to pull the head, since the timing chains have to come off. As of yet, I haven't even cruised thru the shop manual to get a feel for what all is involved. Worst case is having to pull the entire engine like for most major FWD tranny rebuilds. Unfortuantely, if it is what it is, I have no choice.

fool-Moon design: Please explain how the computer could make the valve train sound like a disel with a bunch of ball bearings rattling around in the cylinders? Are you thinking that what I'm hearing is just "knocking" due to a timing issue rather than valve train problems?

bk94si: The valve train noise started few days ago. Wasn't there before. Went thru this site looking for answers. Came across three things of note:This level of clatter was NOT present until just recently - up until the last week the engine was quite and smooth (for a 4 banger).

nacademus: Don't know if it could be "... the exhaust cam sensor and housing clattering ..." The noise is definitely coming from the upper area of the engine (ie valve cover) with the aircleaner removed. The misfire DTC I mentioned indicates #1 all the time, and the noise seems loudest at the driver end of the engine - is that where cylinder #1 is located? Do you know where this exhaust cam sensor is located on our beasties?

Would a compression check be of any use in verifying a valve lifter/follower problem?

THX again all - this is a horrible situation for me right now - got laid off in November so $$$ is more critical than usual.

socalHHRguy

843de: I apologize for any sloppines in my terminaology. When I use the term "valve train", I'm trying to desribe the entire head assembly, which in our case will include two cams and a bazillion valves with their individual followers. (How many valves per cylinder does the 2.2L version have?)

Your thoughts about the " cam followers are gunked up and sticking ..." is my conclusion as well, due to the oilfilter blow out/not changed as often as it should have been issue. I don't know how long the oil has been passsing through the blow outs, since I figured I was geeting a new one each time I paid for one. (California Bureau of Auto Repair will be contacted shortly.)

WRT time between changes, I've been doing 90% freeway crusing so the oil has stayed pretty clean. I've been changing the oil at the 85 to 95% point on the DIC readout rather than using miles as a guide. This methodology was per the local Chev Service Dept Staff.

One of the posters on another thread suggested the MM Oil tretament, so that's what I've done initially to try and unstick the followers.

Since it's got 100K miles on it, it's due for a set of plugs - could a bad plug be casuing both misfire AND the loud knocking/clatter? Still getting 27.8 mpg AVERAGE and 31 - 33 on long, constant speed freeway cruises.

socalHHRguy

Just to be precise here, my vision of doing a valve job is ME pulling the head, carting it off to the local machine shop and having THEM do the disassembly, check for head warpage, cleanout, parts replacement, valve grinding and re-assembly. Quote is $200 to $400 depending on damage .....

843de

The 2.2 is a 16 valve engine so 4 valves per cylinder, and cylinder #1 is the one farthest to the left as you face the engine. A bad plug could give you a misfire but I've never had one really set up a clatter unless its loose in the head, always a possibility though. I'm not sure if you've read the plug threads but I stick with AC Delco plugs just to be safe, so many have had issues with Bosch and other brands. I'd try a plug change first and see if that eliminates the misfire, if not you may have a bad injector on that cylinder. This really does sound like a follower is stuck, but if it doesn't clear up after a few hundred miles it might be time to think about pulling the head. Another thing to consider is doing another oil change in about 2-3,000 miles in order to get the gunk loosened up out of the engine before going back to a longer change interval.