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Vx N/A V6 Ecotec Rough Engine Diagnosis

Gw33dz

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Bought this car for a few hundred, was running well. Drove it home about 350km's.

Next time i cold started it, it was running rough, like 1 or 2 cylinders weren't firing.

I also noticed it was losing coolant and that there was oil deposits in the radiator, kinda thick like greese (not the usual mayo)

I replaced the spark-plugs, 2 of the coils, DFI Module and leads.

Then i replaced the lower inlet manifold gasket and put new filter baskets/o-rings in the injectors while i was there. Both water ports had the mayo in them so the gasket was obviously stuffed.

It was still running rough so i assumed it was losing compression in a cylinder or two.

So I replaced the head gaskets/bolts. Used the pushrods in the same positions but didn't set lash on the rockers. The head gaskets weren't visibly blown.

There was heaps of sludge in the heads which i cleaned out.

I noticed when replacing the fuel rail, the injectors didn't line up properly, so a couple are at a little bit of a weird angle.

All the vacuum hoses, EGR hose, Electrical plugs are connected.

Just wondering what you guys think the problem could be, it's running rough like a couple cylinders aren't firing, not just at idle, but with acceleration as well, the engine has done 350,000km's.

The only things i can think of is an injector or 2 is electronically stuffed (unlikely because the engine was running ok until it was cold). Stuck or stuffed lifters. Not sure.

Any help would be greatly appreciated.

Here's pics of the inlet manifold goop and a ton of goop left on both rocker covers

20200529_133705.jpg 20200530_121035.jpg
 
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BowTie

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Lifters are noisy as when stuck.

Wet/dry compression test?
 

Not_An_Abba_Fan

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Are 100% sure you have the leads on correctly?
 

Gw33dz

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Just double checked the leads, all good. Just ordered a compression tester. Is it possible the rings have gone on a cylinder or 2?

I wanted to let it run for a while and get to operating temp, but it had a coolant leak in that weird heater pipe that goes through the tensioner. I just fixed it, so i'll try tomorrow.
 

Not_An_Abba_Fan

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You say you replaced 2 of the coils, what about the other one?
 

Gw33dz

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The other coil looked quite new. I tried the other 2 older coils in that same spot to double check it wasn't that coil either, engine sounded the same.
 

Dak

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I noticed when replacing the fuel rail, the injectors didn't line up properly, so a couple are at a little bit of a weird angle.
I'd be checking why this is happening, also were the lifters always that noisy?
 

Gw33dz

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No. The engine was running smoothly when i drove it over here, started running rough after a cold start.
 

Trevor loves holden.

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Did you do all the bolts up to specs, with that amount of coolant in the engine it may be stuffed depending how long it was running like that. If the compression is good then be best to replace the lifters. Last time I changed my injector filters and o-rings they went in ok, some do face on angles so it might be normal only you can see if fuel is leaking. Oh wet O2 sensors can make it run rough but you need to sort out the lifters, probably buggered due to coolant.
 

Trevor loves holden.

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If it was running smooth before you removed the rods then something hasn't been put on right unless the pump is blocked and starving your engine of oil.
 
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