V6 Ecotec Dead??

[markbaja]

Hi guys, been a while. Got an issue that I'm hoping to fix pretty soon.

Was driving to work, sitting on about 1500rpm when the V6 dropped to 5 cylinders. Really rough running and stalls on idle.

So I did the "basics" like plugs, leads coil pack swap with one on a working car etc to no avail. Tried unclipping injector leads one by one and the one that made no difference was number 5 (rear most passenger). So a set of reco injectors and still the same. Borrow a compression tester and cylinders 2, 4, 6 and 1 and 3 have around 170ish but number 5 had zero!! Tried all 6 5 times over and over and 4 times got zero and once got 30. Tried teaspoon of oil in plug hole and still getting zero. So what next? Bent valve? Broken valve spring? And is it easier to just replace head? Car has religious 10 thousand services and has 190 thousand on the clock.

Mark

 

[acarmody]

Take off the passenger rocker cover and see if the rockers and valves are moving with the engine rotation. So remove all your spark plugs and manually turn the engine over with a socket on the crankshaft bolt and watch the number 5 valves.

 

[markbaja]

Thanks mate. Took rocker cover off and number 5 inlet spring is in half. Turned engine over with socket and wrench and it doesn't quite come up all the way though not too far down to have smashed a valve. Engine turns nice and smooth with no plugs in, and no mechanical broken sounds (though I don't know if you could even tell like that honestly). Holden have individual spring for $35, and I have someone who has a spring compressor tool. Any advice on tackling the job on the weekend??

 

[acarmody]

Its an easy job. I have taken springs off before, just be super careful when compressing the spring. I had one of those Kincrome overhead valve spring compressors and the arms 'widened' while compressing the spring and slipped off, spring shot up, hard. Thankfully I hadn't yet got my fingers in there to remove the locks. I bent the arms in a bit so that the arms were perpendicular to where they touched the retainer.

Also make sure that you have a way to keep the valve up when you remove the spring. Easy trick is to remove the spark plug, rotate the engine so that the piston is all the way down and feed some rope into the cylinder (use some good fabric rope, not cheap shitty synthetic) and then rotate the engine to raise the cylinder, don't force the engine. If the engine doesn't want to turn any further, don't push.

 

[markbaja]

Awesome mate. Thanks heaps. I'll let you know how I went.

 

[markbaja]

Just to finish thread off. Spring is in place and engine working as it should. Used the trick of some rope in plug hole, and the whole job took half an hour. Anyone needs assistance I'm now an expert lol. Thanks for the advice.

 

[MiKExAUS]

that's awesome mate, well done! Must have just been a defect in that particular spring... Makes me think that the ecotec is a non-interference engine. Can anyone confirm this??

 

[markbaja]

that's awesome mate, well done! Must have just been a defect in that particular spring... Makes me think that the ecotec is a non-interference engine. Can anyone confirm this??

Hmm can't be sure. Valve was coming back up, just not all the way which caused no compression.