Cold Start (After 4+Weeks)

[harks]

hey guys,

i couldnt find anything specific to this so here goes.

i regularly have to travel for 4-8 weeks at a time with work so its not uncommon for my 32 GTR to not be started for said periods.. now ive found over the last 9 months, my car is deteriorating in how rough it is on cold start after a break... early last yeah it wasnt a problem, during startthe engine would shake for the first 3-5 seconds (while i assume it properly lubricated itself) and most recently after 6 weeks from christmas swhen i started it, it didnt just shake it sounded like something clanging within the engine, i was instantly about to cut ignition, however after 2-4 seconds the clanging stopped and she sorted herself out... my car runs perefectly smooth at all other times.

is this a problem (obviously not ideal), and is there anything i can or should do to avoid it, either before i leave or prior to starting? the oil is changed every 4000k or therabouts so is always in good condition, oil pressure is always fine etc etc.

thoughts?

cheers

Dan

[jjman]

yeah I got this too (the clackety clanging, not the shaking) when I go away n then come back n go to restart the car. so now when i go to restart my car I crank it until it almost fires n then shut it off. I do this 3-5 times which pumps oil around the motor without it coming up to any serious revs and so that when I do let it fire it doesn't make the clackety clunk routine. Having said this it was on my GTST and was most likely the hydraulic lifters needing some oil in them. Nonetheless, It still may fix what your issue is too in some way as the motor would be getting pretty dry after 4-8 weeks. But if it doesn't, maybe look for some more extreme elements of wear in the motor...

Beyond this, it sounds like your car is struggling to get fuel or spark to a cylinder for a bit hence the shaking (sounds like a misfire).

Edited January 18, 2014 by jjman

[GTRPSI]

Sounds like your fuel may be bad from sitting so long in the tank, and or the plugs are a little fould from spending the majority of their time running on bad fuel or a little rich while warming up.

Id put some fresh fuel in and a new set of plugs first and go from there.

You could also have a case of a sticking gummed up injector from sitting there for so long.....

Edited January 18, 2014 by GTRPSI

[zebra]

Next time, Pull the plugs out and the fuel pump fuse.

Crank the motor until you have an oil pressure indication on the gauge.

Then refit plugs and fuel pump fuse, and go.

[BrynDETT]

or an easier way, just unplug the cas... car wont fire without it... i do this after every oil change to get the oil flowing...

[Ben C34]

Actually removing the spark plugs is best, as it removes the load on the bearings due to compression. Pretty important on a fresh build, but probably overkill in this instance.

[Missileman]

The rough running is typical of sticking injectors, regular use of injector cleaner will help.

[harks]

thanks for the responses guys!

so to sum up this is either caused by oil draining from the cylanders, or my plugs have fouled from bad/stagnant fuel?, and so by either removing spark plugs or CAS when first turning it over (untill guage registeres oil pressure) then refitting will prevent this happenning in future? (cant really do anything about fuel as i cant replace the fuel without starting her up and taking her to a servo).

if i wasnt to do this, will it damage the engine? or would the wear be negligible?

[jjman]

The rough running is typical of sticking injectors, regular use of injector cleaner will help.

this is true.

if you are still running the stock OEM R32 GTR injectors then id say you would be very wise to upgrade to some new and or bigger ones + tune.

bad injectors are as quick a way to kill a motor as a bad fuel pump- well almost...