VX Engine start up Vibrations

[NateMcNate]

Hey guys,
Started the VX V6 this morning and noticed very bad vibration/shake from the engine for the first 30 seconds after turning it over, only did this from a cold start, warm start was no vibration at all.
Im not sure if its the mounts, fuel, oil or something else.

I use
Catrol Mag 15-40
Shell 95 Unleaded (98 every 3rd or 4th fill)
Cant see anything wrong with the mounts just by looking but they they have never been replaced before(180,000km).

Any suggestions would be great.

Cheers
Nate

[Killr6]

could be the fuel pump getting ready to go.

[VX EXEC 3.8]

Does the fuel pump have a noticeably loud squeel when its running?
They seem to become noisy before they die.

[NateMcNate]

haven't noticed any new noises coming from the engine bay, everything seems the same except for the vibrations, basically the whole car shakes for around 30 seconds when starting cold unless I give it some revs.

[NateMcNate]

Could it be that some of the spark plugs arn't firing? I'm out of idea at this point and hope it isn't the fuel pump.

[Cashman_309]

I'd look at the usual stuff.
Even if none of these are the problem its good maintenance.
Check and/or replace plugs and leads.
Change fuel filter.
Clean MAF sensor.
Clean throttlebody and IAC <<< I'd strongly recommend doing this if your car is high km's or goes long intervals between services.
The last 3 will cost you jack all to buy the products necessary so get to it!

[NateMcNate]

Ok started it this morning with no problems, I will still give those parts a good clean and change the plugs, have to change the fuel line too, cracked the connector to the filter

[NateMcNate]

I found that some sparkplugs wern't firing, changed them all up and 150% improvement, the plugs that came out looked factory but not sure.