4.5ltr Petrol/Gas smoking on startup

[ozzymalone]

Hey folks,

My 98 GU 4.5 is smoking on startup (greyish colour) & not sure as to what the cause is. It has been "resting" in the drive for a week and hasn't had a good drive for about two weeks. Should note too that i am starting it on Petrol not gas.

Had it recently serviced and given the all clear but doubt the mechanic's ability (as it was the day before easter break when it was serviced), and when I got it back they hadn't replaced the power steering fluid which was brown! - (Am I expecting too much from a minor service?) They did change oil though, LOL.

As I only recently got the "wagon" i am not completely across the motor yet but spend a couple of hours each week crawling under the old girl, so any input will be growse! :bananarock:

[Bigrig]

Hmmm ... hopefully if it's only on startup it may just need the MAF and/or throttle body cleaned and/or new plugs and leads. I've read about valve stems going in the 4.5 every hundred thousand or so also, but know little to nothing about that - hopefully someone else will chime in with some ideas also.

Give the MAF and the throttle body a clean up (CRC MAF cleaner for it, throttle body cleaner for that - they're not the same ...) and see how that goes ..

How long since the plugs were changed??

[ozzymalone]

I'm thinking a while but no proof BigRig.......silly me. Had been looking at the might GQ 4.2diesel manual and all my research was on that particular mod till my wife decided that the GU was "prettier" and she wanted to drive it (auto only...GRRRRR!) so when this one popped up and looked clean and seemed to run beautifully I sold it to myself without being objective! Was just too damn excited!

Reckon the plugs might be worth a look @ after I read the workshop manual @ find out where and what the MAF is LOL! ...bless my ignorance, i'm still learning.

[Bigrig]

I'm thinking a while but no proof BigRig.......silly me. Had been looking at the might GQ 4.2diesel manual and all my research was on that particular mod till my wife decided that the GU was "prettier" and she wanted to drive it (auto only...GRRRRR!) so when this one popped up and looked clean and seemed to run beautifully I sold it to myself without being objective! Was just too damn excited!

Reckon the plugs might be worth a look @ after I read the workshop manual @ find out where and what the MAF is LOL! ...bless my ignorance, i'm still learning.

Hahaha ... all good mate ... the MAF should be on top of the intake ducting, engine side of the airbox (if the same as the 4.2) ... two screws to take it out and disconnect from harness. Give the wires on the end of the sensor a good spray (not too close as they are delicate) with MAF cleaner and put back in ...

If its given errors to the ECU you might want to have them cleared or disconnect the battery for a few hours overnight to clear them out (just so it doesn't still think the problem is there with the MAF).

[Bob]

hahaha ... All good mate ... The maf should be on top of the intake ducting, engine side of the airbox (if the same as the 4.2) ... Two screws to take it out and disconnect from harness. Give the wires on the end of the sensor a good spray (not too close as they are delicate) with maf cleaner and put back in ...

also disconnect the battery for an hour or so to reset the ecu. 1/2 hour would probably work but the longer the better

[Bigrig]

also disconnect the battery for an hour or so to reset the ecu. 1/2 hour would probably work but the longer the better

Haha - on ya Bob!!! Was editing that in after I hit send!!!! You beat me to it!! lol

[pearcey]

Grey to black smoke is a sign of being rich but on cold start up this is not all that uncommon is there any smoke once the engine is warm.
A minor service is just that minor ie Air, oil and possibly fuel filter change plus oil change, grease all suspension and tail shaft points. CHECK all other levels ie trans, diff`s, power steer.coolant etc . Always change the oil filter at every oil change. If you are usure about the smoke get some one to gas Analise the engine and they should be able to make the appropriate adjustments. Best of luck

[ozzymalone]

And as always...THANKS. You are all gentleman & scholars and , yes, they should pay you more!

[Ben-e-boy]

Mate you need to do a compression. greyish smoke on start up is could be valve stem seals or valve guides, My suggestion is Before compression test) before a cold start remove the oil filler cap and if it blow smoke out through the rocker cover you have valve troubles

[ozzymalone]

Sounds expensive? Not the compression test but the valve dramas.....fill us in Ben-e-boy.

Are you saying just remove oil filler cap and look down into the head an see if smoke is coming up outta the head on a cold start?