Surging Idle speed when Air-Cond on???

[rojodo]

I have an 2005 NP Pajero, 3.2 Diesel, Auto, (MY06), with 115,000km.

Problem: Idle seems to surge every 20/30 seconds when the Air Conditioner is switched on, runs fine at idle with the A/C off.

I have recently had the battery disconnected a couple of times, and have noticed this problem since then.

I have checked the Airfilter is clean, and the Fuel filter has no water or air in the system. Vacuum hoses seem fine.

I did a quick search here; and found some info regarding the 'Idle Air Bypass Valve" on the throttle body (IAC Valve) & the Idle Speed Motor may need cleaning. (I am not sure if this info is relevant for my vehicle, as this info was in regard to a petrol pajero???)

If it is something to do with the above mentioned, what/where should I start. Anyone have a step by step guide to what I should be doing?

A mate told me to take it to Mitsubitsi, to get it tuned.... but I thought I'd have a go first!

Thanks

Ron

[dmr292]

Hi, Not an expert, but i have read on the forum that you will need to leave run for 10-15mins at idle with ac on. It should reset itself in the computer.

Anyway, hope that works

[saj]

I have an 2005 NP Pajero, 3.2 Diesel, Auto, (MY06), with 115,000km.

Problem: Idle seems to surge every 20/30 seconds when the Air Conditioner is switched on, runs fine at idle with the A/C off.

I have recently had the battery disconnected a couple of times, and have noticed this problem since then.

I have checked the Airfilter is clean, and the Fuel filter has no water or air in the system. Vacuum hoses seem fine.

I did a quick search here; and found some info regarding the 'Idle Air Bypass Valve" on the throttle body (IAC Valve) & the Idle Speed Motor may need cleaning. (I am not sure if this info is relevant for my vehicle, as this info was in regard to a petrol pajero???)

If it is something to do with the above mentioned, what/where should I start. Anyone have a step by step guide to what I should be doing?

A mate told me to take it to Mitsubitsi, to get it tuned.... but I thought I'd have a go first!

Thanks

Ron

Hi Ron,

Try these shortcuts, they should help you out hopefully.

http://www2.pajeroclub.com.au/forum/showthread.php?t=18484&highlight=reset+idle

http://www2.pajeroclub.com.au/forum/showthread.php?t=21012&highlight=reset+idle

Good Luck.

[rojodo]

Thanks for the tips, I will try all the methods then post up how it went.

thanks
Ron

[psproule]

I have an 2005 NP Pajero, 3.2 Diesel, Auto, (MY06), with 115,000km.

Problem: Idle seems to surge every 20/30 seconds when the Air Conditioner is switched on, runs fine at idle with the A/C off.

I have recently had the battery disconnected a couple of times, and have noticed this problem since then.

I have checked the Airfilter is clean, and the Fuel filter has no water or air in the system. Vacuum hoses seem fine.

I did a quick search here; and found some info regarding the 'Idle Air Bypass Valve" on the throttle body (IAC Valve) & the Idle Speed Motor may need cleaning. (I am not sure if this info is relevant for my vehicle, as this info was in regard to a petrol pajero???)

It's a diesel so it does not have an IAC valve or motor. Just do an idle relearn. Take it for a drive & get it up to operating temp. Then let it sit and idle with the AC on for about 10 minutes. It will sort itself out. Happens every time you disconnect the battery.

Pat

[rojodo]

Thanks for the help, all back to normal now

Just let it idle for 5 mins without A/C on then for 5 mins with the A/C turned on.

But also did the 10 mins Idle with the A/C on.

so could have been either, anyhow all is good now.

thanks again

Ron