Weird uneven idle on my Gen 4

[Mitsu Fan]

Hi guys.

My 2015 Gen 4 with 75 000 km on has developed a weird idle problem.

When I stop dead at a stop intersection or traffic light the engine idles with a lumpy feeling for about 3 seconds and then goes away. Problem is that this is very infrequent and mostly random.

Some guys point to dirty transmission fluid but the oil change only comes at 100 000 km.

I have done some tests as suggested by selecting neutral just before I stop to see if it persists. But being so infrequent it is difficult to select neutral when it happens because the period is so short.

Any ideas ?

Cheers

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[The Mul]

Hi

I though Transmission Fluid interval was every 60 000km?

Mine has started with the same occasional slight variation in idle speed, I suspect the SCV (suction Control Valve) from what I have read. Min is due for 260k service in 500km, so I will be doing that first (incl new air/diesel filters) and then decide if further action is required

Henk

[CATS]

Maybe top up the diesel tank with some fresh juice as a start. Also make sure the airfilter is nice and clean.

Can't hurt to start with the small things.

CATS

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[RoelfleRoux]

I think your Pajero needs some fresh Barberton mountain air. I can assist with that!!
PS. All Pajeros run better on fBma

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[Mitsu Fan]

Thanks guys.

@Henk I queried this with the dealership after the 60 000km service and apparently the 2014 onwards have a high output transmission which only requires changing at 100 000km. The service book confirms this.

@CATS I will start going through those basic items and see what pops up.

@Roelf I cant agree more. We need to set up that weekend we spoke about last year to go play in the mountains seeing I cannot come in the week to discuss mining machines with your Engineer. Pity......

Cheers

Henri

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[Greg_SA]

I would change the diesel filter and run a new full tank of diesel with the Mitsubishi fuel system cleaner.

If that doesn't work, it is probably the SCV (suction control valve) on the diesel pump. In fact, my money would be on a faulty SCV. They do wear out. The SCV is used to regulate the fuel supply, and when it wears, it can't regulate smoothly, it gets "notchy".

[Bernard]

Hi guys
I have had the same issue for a long time, and in the interim, I have changed fuel filters, air filters and AT fluid, as well as cleaned the throttle body to no avail.
Please advise where the SCV is located and if it is easy to change...

[Greg_SA]

The SCV is quite easy to change - at the bottom of the diesel pump. Only issue is getting your hands down there. Very little space. But it can be done without removing much. I jsut loosened some cable clips/mounts, to get the surrounding cables out the way. You just need to get our hand and an allen key down there.

Also search on the 4x4community for part numbers and photos.

[LowRange]

I have been having a very similar issue the past two months. It happens from time to time that when stationary in "D" the revs will fall very low and result in a rough idling. Switching the aircon on/off makes no difference.

When selecting "P" however, the idling goes to normal. It will do it once or twice, and then 2 weeks will go by with all being normal before it returns again.

Any ideas.

Thanks

Johan

[LowRange]

I have been having a very similar issue the past two months. It happens from time to time that when stationary in "D" the revs will fall very low and result in a rough idling. Switching the aircon on/off makes no difference.

When selecting "P" however, the idling goes to normal. It will do it once or twice, and then 2 weeks will go by with all being normal before it returns again.

Any ideas.

Thanks

Johan

OK, just to leave some feedback here that might be helpful to somebody. Managed to sort the problem on mine.

It seems the Transmission Fluid does not last the 100k km as per the service interval requirements on the Gen 4 when you do a lot of towing! . Changed the fluid and ATF filter - car now running like new again.

Had done 84k km since the last ATF oil change.