Glow plug or injector

paddyman, Oct 17, 7:23pm
in a VX Turbo 4.2 Cruiser, starts a bit rough only when cold. Starts no problem once warm, could it be glow plug or injector. Its done 300km, new diesel pump and possibly original injectors.
splinter67, Oct 17, 7:28pm
if you glow it twice dose it start nicely
gadgit3, Oct 18, 5:16am
12valve or 24valve! as 12valve have glow plugs and 24valve don't I would be leaning toward injector or valve clearance tho from experence.
the-lada-dude, Oct 18, 5:21am
MY choice would be G/Pif you do have to replace some CHECK that the G/P is for the turbo model
intrade, Oct 18, 5:34am
is it puffing white smoke on coldstart but not when warm!
what engine has that got! fitted and what year!
need to kow this answered first as its a big difference on commonrail or idi diesel engine.
mrfxit, Oct 18, 6:50am
Yep if the problem has happened in a reasonably short time frame & if it's got glow plugs, then it's very likely somethings happened there.
Could be any of
Plug failure
Cable break
Fuse blown
OR
Batttery / starter with not enough amps, WHICH in turn again, could be cable /battery or brush problems
Cold start problems but fine when warm are not normally injectors.
mrfxit, Oct 18, 6:54am
Got to sort my own out this week.
Had new g/p's last year & rebuilt injectors last month & THEN suddenly started having harder cold starts just after the injectors were done, warm & hot is 90%. fine (Half a turn on the starter)
If you have a volt meter fitted, then when you turn the ign key to ON, the meter should drop a lot & approx 15 / 30 seconds later will pop back up & you should hear a CLUNK from the g/p controller at the same time.
gadgit3, Oct 18, 7:56am
Problem is the engine would be either a 12valve (1HD-T) or 24valve (1HD-FT or E if EFI) But the 1HD-T hardly even needs the glow plugs it has fitted. Even with the glow fuse pulled it will still start fine. I'd be closly looking at the injectors but seen more with valve clearance issues with rough cold start.
gadgit3, Oct 18, 7:58am
Landcruiser runs a super glow system 1.5 sec the light goes out and max of 10sec run time.
mrfxit, Oct 18, 8:02am
Yep ta for that update & it's still a good start to check with.
See . wasn't far out ;-)
mrfxit, Oct 18, 8:04am
I would have thought that if it's injectors, that they would be in pretty bad condition to behave that badly.
(Engine rebuild coming up when they fall off. anyone!)
gadgit3, Oct 18, 8:34am
A injector that drips after shut down will cause rough start up and can take a few mins to clear. Seen this in 1HZ and 1HD-T
I have seen bad injectors cause ring failer (low compression) in the 1HD-FT and the rough start up clears once the engine warms up. feels like it runs on 5 cyl until warm.
But more common then those two is valve clearances.
paddyman, Oct 18, 2:44pm
Its a 12 valve engine, if it was a valve clearance issue wouldn't it be running all the time!
petermcg, Oct 18, 2:49pm
Is it puffing smoke and what colour. It could be a temperature sensor. A temp sensor may adjust timing as well as set up any cold start procedure within the system.
gadgit3, Oct 18, 3:15pm
Nup 12 valve engine all mechanical no electric nothing lol.
gadgit3, Oct 18, 3:21pm
Not saying it is a valve clearance issue but what I am saying is more often it is with the HD series engines. And yes the running rough goes away when the engine gets up to temp with valve clearance issues.
Do the simple checks first. glow plugs are easy to get to. then valve clearances. if they are ok compression test ok then send them injectors away.
snoopy221, Oct 18, 3:26pm
In a NUTSHELL.
Tight valve clearances can cause VERY low compressions (Due to leaking valves) for about a minute or 2 of running-then the clearances GROW as they warm up.
jmma, Oct 18, 3:35pm
Not sure on this one!
Metal expands when hot, clearances would close or SHRINK IMO (o:
mrfxit, Oct 18, 5:05pm
LOL . Oopps Snoops ;-)

Correct if it ran worse when hot. (most days)
Altho yea tappets CAN be a law unto them selves some days.
Specially when rocker ends get cupped
snoopy221, Oct 19, 2:57am
when rocker ends get cupped

Quotemrfxit (2174 )7:05 pm, Thu 18 Oct #19
Wee el a 10 mill valve and a 40 mil bucket
Wonder whichn bonev warms.!
Mindja cld be a time me nd gdgit rgu.
OR.
meh.
Doubt it.I M H O