Surging or rough idle on start up

[Dalma01]

When I cold start my Pajero in the morning, it surges (lumpy idle) for about 30 secs or so. After that it is totally normal. It's almost like it has a cam Anyone have any ideas. It's driving me nuts.

[Muzza]

When I cold start my Pajero in the morning, it surges (lumpy idle) for about 30 secs or so. After that it is totally normal. It's almost like it has a cam Anyone have any ideas. It's driving me nuts.

Is it puffing white smoke during this time?, if so most likely a dead glow plug

[starjunk]

When I cold start my Pajero in the morning, it surges (lumpy idle) for about 30 secs or so. After that it is totally normal. It's almost like it has a cam Anyone have any ideas. It's driving me nuts.

A guy walks into a bar with a steering wheel down his pants. bartender says:"hey mate, do you realise you have a steering wheel down the front of your pants?"
Guy says:"YEAH! It's been driving me nuts!"
Seriously though.... If not glow plugs it could be injectors... Though the smoke would go more than 30 secs and it would run rough even after 30secs too... So tend to agree with the glow plug idea. Easy to measure the resistance, and identify the culprit (as long as you remove the busbar of course) from memory they are about 1.8 Ohms... Well very low resistance anyway, when they are good.

[Dalma01]

Is it puffing white smoke during this time?, if so most likely a dead glow plug

Thank you Yes big plume of white smoke.

[Dalma01]

A guy walks into a bar with a steering wheel down his pants. bartender says:"hey mate, do you realise you have a steering wheel down the front of your pants?"
Guy says:"YEAH! It's been driving me nuts!"
Seriously though.... If not glow plugs it could be injectors... Though the smoke would go more than 30 secs and it would run rough even after 30secs too... So tend to agree with the glow plug idea. Easy to measure the resistance, and identify the culprit (as long as you remove the busbar of course) from memory they are about 1.8 Ohms... Well very low resistance anyway, when they are good.

If I don't glow plug it. It starts worse. Would that mean maybe just 1 of the glow plugs is gone?

Thanks for the info, I will get my multi meter out this afternoon.

[shawty950]

Check +ve terminal 1st

Nephew has an NW.... didn't come and see me 1st...had same symptoms, white smoke on startup.

Mechanics charged $1200 for service and new glow-plugs...said 1 was broken...

Gets it back and it's still doing the same...no change...he was devastated....I get him to come over and we start going thru the basics...fully expecting a fusible link to be gone (the bank of three on the positive batt cable) (quite common when ham fisted mechs leave ignition on and ground the glow plug plate)...or the glow plug relay....1st things 1st, check battery terminals...+ve was loose.

Pull terminal off and see that the battery post had been eaten away where the terminal contacted due to bad contact and it had been arcing under load.

So we clean the terminal up and re seat the cable properly and all fixed...exactly 10mins to identify and fix...+1 beer.

Dont know the specifics and cant find it on the russian manual website atm...but the glow plug system when it cranks up draws a large amount of amps ( iirc ) and loose terminal was arcing, the glow plug system was not getting full black magic stuff and therefore smoke on startup and lumpy idle until the cylinder temps rose to fix itself.

It might be something more sinister...the glow plugs may have gone, 1 or many...but check the obvious 1st.

Nephew has an optima battery and the terminal post is a little on the small side for the OEM terminal, hence why it was not tight enough and caused the problem...we modified it a little so that it could get more bite/adjustment.

[starjunk]

Agreed, glow plugs need good current supply. On my NJ I changed the cable to get the plugs working properly, as the factory one was severely oxidised.

[Dalma01]

Nephew has an NW.... didn't come and see me 1st...had same symptoms, white smoke on startup.

Mechanics charged $1200 for service and new glow-plugs...said 1 was broken...

Gets it back and it's still doing the same...no change...he was devastated....I get him to come over and we start going thru the basics...fully expecting a fusible link to be gone (the bank of three on the positive batt cable) (quite common when ham fisted mechs leave ignition on and ground the glow plug plate)...or the glow plug relay....1st things 1st, check battery terminals...+ve was loose.

Pull terminal off and see that the battery post had been eaten away where the terminal contacted due to bad contact and it had been arcing under load.

So we clean the terminal up and re seat the cable properly and all fixed...exactly 10mins to identify and fix...+1 beer.

Dont know the specifics and cant find it on the russian manual website atm...but the glow plug system when it cranks up draws a large amount of amps ( iirc ) and loose terminal was arcing, the glow plug system was not getting full black magic stuff and therefore smoke on startup and lumpy idle until the cylinder temps rose to fix itself.

It might be something more sinister...the glow plugs may have gone, 1 or many...but check the obvious 1st.

Nephew has an optima battery and the terminal post is a little on the small side for the OEM terminal, hence why it was not tight enough and caused the problem...we modified it a little so that it could get more bite/adjustment.

Awesome reply, thank you. I have changed the battery, because it went flat to an optima with new terminals cause like you said, original didn't fit right. Cranks like it's on steroids.
Unfortunately, It still does the same

[Rooster]

Going along Shawty's line, My NW recently started to suffer from slower / harder starting with white smoke and finally gave me more grief on a cold Canberra morning. The battery was not the issue as it cranked fine. After returning home and when the air bag was replaced I mentioned it to the dealer. They found and rectified a corroded connector to the glow plug or plugs (not sure which) but whatever they did sorted the issue.

[Dalma01]

Going along Shawty's line, My NW recently started to suffer from slower / harder starting with white smoke and finally gave me more grief on a cold Canberra morning. The battery was not the issue as it cranked fine. After returning home and when the air bag was replaced I mentioned it to the dealer. They found and rectified a corroded connector to the glow plug or plugs (not sure which) but whatever they did sorted the issue.

Could very well be that. It spent it's first year in Port Maquarie.

[psproule]

If it's clouds of white smoke at startup then I'd suggest a leaking injector tip.

[Dalma01]

If it's clouds of white smoke at startup then I'd suggest a leaking injector tip.

Would you have to put it on the bench to check?

[Netfox]

If I don't glow plug it. It starts worse. Would that mean maybe just 1 of the glow plugs is gone?

Thanks for the info, I will get my multi meter out this afternoon.

Did you check it with the multimeter?
If resistance is good for all plugs, check if adequate voltage is getting there.
Voltage drop should be less than 0.5V between battery and glow plugs during glow cycle?
Hope you get it sorted.

[Dalma01]

Did you check it with the multimeter?
If resistance is good for all plugs, check if adequate voltage is getting there.
Voltage drop should be less than 0.5V between battery and glow plugs during glow cycle?
Hope you get it sorted.

Will be checking them today. My multimeter grew legs so will have to buy another one today.

[Dalma01]

Went to buy a multimeter yesterday. Fire up the Pajero...and all was good. No rough idle or white plume of smoke. Looked at the outside temp and it was 14. Got back and checked glow plugs, and all was good

Checked connectors, they were ok. Must be some sort of glow plug problem, as it goes away when it was warmer temp.