Rough idle on vt

[YoutubeTrainedMechanic]

Hi i have almost had it with my car I replace one thing and find another problem
Im no mechanic this is first car ive worked on
So it started with a blown head gasket bought a vrs kit replace all the gaskets in the top end of the engine
Got a mechanic to do a engine flush
Put on new oil filter
i serviced the injectors
replaced the spark plugs and leads
Got a new starter motor
Bought a coil pack to check all the coil packs got zapped. They were all fine.
Then after all this, the engine had a squeak when it was running so replaced the water pump.
This caused the radiator to split one of its plastic outlets.
So replaced the radiator. ran the car for half a day and it split the heater tap hose.
so thought stuff this ill buy every hose and replace them
by now i am at the point of where i have put to much work into it to sell it
Went to put on the new hoses just to shatter the brittle heater tap bought that replaced it
just ordered 2 oxygen sensors hope they come tomorrow

So this is what i have done so far,
it runs really good when it is driving but idling shakes the car and when i put it in drive to get going there is a slight pause before acceleration this is only after starting it.
It starts on first turn over
i can also here the engine tapping
Any ideas?

 

[jeepyrocks]

has the throttle body been cleaned out? Check that first. A filthy EGR and IAC (both connected to the throttle body) will cause idle issues. I'd also check the engine mounts - if they have slumped on to the subframe she will feel rough as guts.
Be happy its a VT V6 - one of the easiest motors to learn and work on.

 

[SavVYute]

You'll never get a truly smooth idle with an ecotec. It's just the nature of the beast.
But it shouldn't shake the car at idle.

A slight air leak in one of the engine hoses maybe?
See how the new oxygen sensors go.
Check the engine mounts.
Also possibility a previous owner might have fitted the cheaper solid rubber type mounts in place of the smoother/softer/more expensive factory original oil filled type.
What grade of oil are you using re the tapping sound?

 

[NeddyBear]

How many Ks had the VT done before you purchased it?

Engine tappet tapping is normal with the high K Commodores and it's because as the valve pushrods wear its not possible to adjust the tappets like we could with the straight 6.
Unless there sounding like chaff cutter then there fine. The Nulon 20W50 high KLM oil and the Nulon Lifter Free & Tune Up will go a long way to quieting her down.
As for the rough idle, this could be everything breathing and fuel related. We had a slight rough idle issue and replaced all the sensors and she now purrs like a big pussy.
Another thought is have you put any injector cleaner in the fuel tank recently and this is a must give the throttle body and parts a good cleaning, either use the throttle body cleaner spray or if you're capable then pull it apart and give it a decent cleaning that way. Also as the others suggested change the engine and transmission mounts, this is a prick of a job so maybe take it somewhere to have this done and what I do when getting stuff like this done is to buy the quality parts beforehand and have them fit your parts and also ask them to put the old parts in the boot so you can check that they have actually replaced them.

 

[devilly]

take engine cover off and then start car and put your hand on top of the block see what you feel.also can carefully put hand on sump see what you feel.