4jg2 rough idle / sensor question

[JustinWNZ]

Hi all
I have just rebuilt the top end of my 95 bighorn and treated it to a new turbo and lower milage parts, now back together it white smokes on idle and surges up and down.
Under power it seems ok.

I think it might be something to do with the preheat system perhaps?
I have a plug at the front which is a water temp sensor i assume for the system which is unplugged, not sure why but can anyone tell me where this plugs into and where it goes?
Attached image of the plug circled.
It could be ive just missed in in the part of the loom that goes to the other sensors there perhaps?

Any help would be appreciated.

Cheers
Justin

sensor.jpg

[JustinWNZ]

Found the sensor plug! (YAY)
But still idles rough and whitesmokes.

Whats casues this?
Apart from bad injectors?

Cheers
Justin

[geeves]

white is most often water but can be diesel or oil. What does it smell like? Was the head new or second hand?

[JustinWNZ]

white is most often water but can be diesel or oil. What does it smell like? Was the head new or second hand?

Head was second hand, I took it off a wreaked engine as i bought a whole spare truck. - No4 was blown just after they had trying to figure out why it was losing power..
So had most bits replaced before hand.

Hard to start when cold which makes me think its not water? - not sure? - I will give it a sniff and see if it smells collant like.
New gaskets through out so i would hope its not the headgasket leaking...

Cheers
Justin

[JustinWNZ]

Nose is a bit blocked hard to tell what it smells like.
Took the radiotor cap off a few small bubbles come up - not a good sign is it?
If its left idleing it seems to get worse and worse.

PLus side is with the other connector on it wasnt so hard to start

Cheers
Justin