Cold start idle

[SilasStingy]

Sorry this may be a long shot but it's not the starter motor getting lazy is it? (Wearing out).

This is not during the starting sequence, it starts immediately. It's only during idling. For example when stopping at red lights.

 

[jonela]

So just a quick recap, it only dose it from cold,but disappears when the engine is warm ? if so dose it stop once the thermostat has opened ?

or dose it persist when warm on idle ,like you say at lights etc?

If when warm you put it in neutral and let it tic over dose it struggle for a few seconds and then return to normal 750rpm ?
John

 

[rustic]

Automatics have some peculiar sensors and switches that link into the control system, as a Manual man, I am not familiar, but I am always amazed when people say... it won't do this or that in Neutral, but only in Park, unless it's a Sunday or something like that. lol:lol
So maybe that's why there are differences, in your revs, but don't ask me why lol...

 

[Lazy-Ferret]

Most times, idle issues on a car that runs fine in most other ways, seem to come from a switch issue or a temp sender fault.

I would do a search on here, and check the Temp sender values on the engine, make sure they are reading the correct values, then check the Neutral switch on the gearbox, maybe it's sticking when the gearbox is cold, and not sure if the 3.0 had it, but the Crank position sensor could also cause this.

These are all pretty easy to check with a basic meter, and the info on the correct values is in the workshop manual download.

http://www.nissan4x4ownersclub.com/forum/showthread.php?t=25474&highlight=gearbox+switch&page=2

 

[SilasStingy]

OK cotton bud dipped in spirit very gently wipe the two wires, they are spiral wound on a ceramic core, on the inlet side it will probably be black with debris, Rick

I did this on Wednesday and since then no problem!

 

[solarman216]

I did this on Wednesday and since then no problem!

Guessed it was the maf, well done, Rick

 

[SilasStingy]

Now the problem has started again! Cleaned the MAF once again with no success... Still after driving for a while it will get better. Guess it's the MAF that has failed as it did get better after cleaning it the first time?

 

[SilasStingy]

Got a new MAF yesterday from eBay. Plugged it in with no effekt on the idle. Noticed as well that there seem to be no difference if i unplug the MAF entirely, still idles the same. I have a new CPS, will change that one as well just to see..

 

[Banshee]

Strange!!!!! My Maverick wouldn't run at all without my MAF being plugged in and that was a Hitachi job

Just for future reference I did a workshop download on this :thumb2
http://www.nissan4x4ownersclub.com/downloads/workshop/wk48.pdf

Are you 100% the plugs are OK? I never trust the multimeter test, I always whip them out and do the jump lead test, if you can see them glow you know they work :thumb2

I know they say numbers don't lie but I don't trust numbers :lol

 

[SilasStingy]

Strange!!!!! My Maverick wouldn't run at all without my MAF being plugged in and that was a Hitachi job

This is very strange, that's what I also though so was surprised when there where no difference even with the MAF unplugged..
I have a spare CPS so will try to change it + go trough the glow plugs once more.
Is there an EGR valve on this model, can that one be the cause?

 

[terranosaurusdoug]

Hi there, I'm no expert but if it was my motor I would check or maybe just replace the engine temp sensor as suggested by lazy-ferret!!
Like it says in guide for checking glow plugs on here, the glow plugs keep heating after engine is started, for ten minutes or until temp gets to 50!
Sounds to me like your plugs are not doing this so causing a rough idle, hope this helps, Mark :thumb2

 

[solarman216]

This is very strange, that's what I also though so was surprised when there where no difference even with the MAF unplugged..
I have a spare CPS so will try to change it + go trough the glow plugs once more.
Is there an EGR valve on this model, can that one be the cause?

on UK models it varied as to EGR yes or no, not related to year or model, so if you have one, you do if not you do not, to check, if you have one you will have 25mm diam approx S/S pipe from inlet manifold to exhaust pipe, and yes if you have one and the valve is passing it will have an effect on idling, Rick

 

[SilasStingy]

Hi there, I'm no expert but if it was my motor I would check or maybe just replace the engine temp sensor as suggested by lazy-ferret!!
Like it says in guide for checking glow plugs on here, the glow plugs keep heating after engine is started, for ten minutes or until temp gets to 50!
Sounds to me like your plugs are not doing this so causing a rough idle, hope this helps, Mark :thumb2

So have ordered some cheap plugs from ebay and an Engine temp sensor from a local shop. If the plugs is the issue then I will consider buying the good quality ones.
We have -14ºC here now and the car starts with no hesitation. The engine is revving faster due to the cold and only get lumpy when starting to reach temperature and automatically lower the revs...

 

[terranosaurusdoug]

Well I hope you get it sorted soon, -14 is not weather to be tinkering in :lol