Engine hunting/surging

[shan_b]

Hi Guys, so as the title reads, I'm having an engine surge/hunting issue. Now it is nothing too major but obviously I'd like to nip it in the bud and ideas are always appreciated.

Here's the details.
2012 2.5ltr
55,000k's (yeah I drive far to work)
at 50,000 did the fuel, air and oil filter.
No obvious signs of leaks.
EGR is blocked (has been for a long time)

Here's the problem.

The engine seems to hunt in a rhythmic sense for +/- 100rpm when the engine is NOT loaded up. I should mention that its not abrupt or violent but just not smooth. It does this when the revs are around or slightly under 2000 and mostly so in second and third, but it might be in every gear. Like when you are sort of coasting at say 40Kph in second
seems to only happen when warm.

Tonight I will put a full tank of diesel in with some Morey's diesel smoke killer. I will also run the OBD scanner and see if anything comes up.

All other help and ideas appreciated, and obviosuly I am starting with the cheap and easy 'solutions' first
P.S... Please don't scare the shit out of me with fuel pump horror stories

Shan

 

[camo.b]

I have the same problem with a d40 king cab but only in 4wd

 

[shan_b]

1 problem at a time! lol

I hope that yours (and mine) are nothing serious mate!

 

[camo.b]

Has yours always done it...or 8s it somthing new?

 

[shan_b]

Im thinking it's something new, I think it only started a couple of weeks back, the trouble is, it has been so windy down here in VIC that it was impossible to tell if it was the car doing it or not

 

[bods]

Try the neutral position switch. Does your heat switch work properly? It should bump up the revs in neutral but drop down to normal idle rpm in gear. Try looking at that first. They do cause surging issues if they are faulty. You can either replace it, or if you have no need for the heat switch just unplug the wire from the nps on the side of the gearbox...

 

[nathand22]

As above it sounds like the neutral position switch which is VERY common for the D22, it happened to mine and many many others.
I f you pull the boot of the shifter in side the cab so you can see the top of the box you will see a blue plug, just disconnect it and go for a spin if the symptoms go you have two options,
1)leave it , as i did.
2) replace the switch, really not necessary but its up to you.

 

[shan_b]

Thank you all for your advice.

Yesterday I put a full tank of diesel in, some of that Morey's and checked that there were no engine fault codes...

Believe it or not, I think the issue has resolved as there was no surging yesterday or today. I didn't think anything in the fuel system would clear up that quickly, so I guess I'll keep an eye on it.

I'll also keep the NPS in mind, although at the moment, my heat switch works fine

Thanks again guys

Shan

 

[henrymyapi]

hi all i have a simalar problem my car just started surging at all rev ranges have repalced all fillter and droped and cleaned the tank as where i am we get a lot of bush fuel but the problem is still there but not as bad any advise would help me a great deal as we are 200 km from any workshops
thank you

 

[nathand22]

hi all i have a simalar problem my car just started surging at all rev ranges have repalced all fillter and droped and cleaned the tank as where i am we get a lot of bush fuel but the problem is still there but not as bad any advise would help me a great deal as we are 200 km from any workshops
thank you

try unplugging the neutral position switch, it wont hurt anything and you have nothing to loose by doing so, its only purpose is to drop the revs back to idle when the car is in gear while the "heat" switch has been activated to prevent any problems from high revs and clutch being released.

If it is still surging with it unplugged at least you will have ruled out the NPS being the problem.
It could also be the "MAFS" (mass airflow sensor)

 

[webby48]

G'day Guys, I'm also in need of some help with surging issue in my 09 d22 2.5cr, drained fuel filter all ok still surging to the point now when idling it sometimes stalls, driving at normal speed not to bad but feel its bit down on power concerned about dirty fuel but any other thoughts would be great before it gets taken to nissan! Thanks in advance

 

[Cgrigg]

Hi Guys, so as the title reads, I'm having an engine surge/hunting issue. Now it is nothing too major but obviously I'd like to nip it in the bud and ideas are always appreciated.

Here's the details.
2012 2.5ltr
55,000k's (yeah I drive far to work)
at 50,000 did the fuel, air and oil filter.
No obvious signs of leaks.
EGR is blocked (has been for a long time)

Here's the problem.

The engine seems to hunt in a rhythmic sense for +/- 100rpm when the engine is NOT loaded up. I should mention that its not abrupt or violent but just not smooth. It does this when the revs are around or slightly under 2000 and mostly so in second and third, but it might be in every gear. Like when you are sort of coasting at say 40Kph in second
seems to only happen when warm.

Tonight I will put a full tank of diesel in with some Morey's diesel smoke killer. I will also run the OBD scanner and see if anything comes up.

All other help and ideas appreciated, and obviosuly I am starting with the cheap and easy 'solutions' first
P.S... Please don't scare the shit out of me with fuel pump horror stories

Shan

Hi all I am seeing the same thing on my 2014 stx d40 550.

 

[fuzzylogic]

possibly the suction control valve? (SCV) This thing is supposed to regulate fuel to the injector pump, your symptoms sound like this is the culprit...

 

[Billy54]

I had a hunting problem with the engine and fixed it with 'Fuel Doctor'. Good stuff! breaks down dirty fuel [Diesel sludge] I get it at Supercreep when on special [half price]