Hi all, before i describe the problem, I'll tell you that I have an intermittent fault with the dett. sensor which I have re-located to ther upper plenum in the usual place, which sometimes doing a diagnostic reads 55, sometimes 34, i don't know if this could be a factor....

 

The car idles perfectly until warmed up fully, then starts to drop to about 600 rpm for 1 sec ish, then up to 1100 for a sec ish, and keeps doing that for about 30 secs, seems to sort itself out, then does the same again about 10 secs later, but revs and drives fine, until i stop and set off again, then hesitates before going, then fine (it's an auto)...

 

Perhaps a vacuum leak somewhere? I would of thought if it was, then it would do the same when cold, but only does it once fully warmed up... If it is, what's the best way to find it? Seeing as there are plenty of vacuum pipes to choose from :-(

 

Any help is appreciated guys, and I'll be fixing the dett. sensor prob soon, gonna use my initiative, as can't afford a new look just yet :-)

 

Cheers...

I also hear what sounds like a leak, which changes with the idle, coming from the front left, under the in/out pipes to the plenum, but could just be the bearing on a pulley, but does sound alot like a hissing sound, i removed the pipes and everything seems hunky dory, although i did change a couple of pipes, just for the sake of it....

 

Does anyone with this problem live near bolton? I can't drive mine as she's not MOT'd etc yet because of this!!! :-( :-(

 

I'm 'cracking' on with it soon, so wish me luck....

Does anyone with this problem live near bolton?

 

I do have an idle problem though not sure if it's the same issue you guys have or not!

 

Mine doesn't stall but won't sit at the 750 rpm that it should, sometimes it's 2000 sometimes it's 1000 but it seems to make it's own mind up!! When cold it's mainly around the 2000 - 2500 mark!!

 

I'm in Wigan by the way if i can be of any help (not saying that i can be though :wack: ).

 

Cheers

OneSHOT

also forgot to say, when it's doing this it can pull up a rather steep hill in second on idle!! :eek:

Im taking off my dump valves on chrismas eve, and hiring an elf to get his little hands down the back of the air regulator to remove it for me

Is 750 rpm the normal tick over speed? when mines not playin silly beggers, it's around that mark, i thought that was a bit slow?.........

 

Cheers Oneshot, I'll bear you in mind, i didn't get chance to have a look today, arrrghh, so will be tomorrow, i think i'll start with the idle control valve, clean that up and the connections, and go from there......

yep thats about normal

Cheers, that's nice to know, at least something is normal some of the time, haha......

tudor i sorted my idle prob by the following..

using the throttle cable tightner i adjusted the idle to about 1300 ish

then untightned the throttle position sensor and moved it about till it idled at about 800 tightned it up ...now all it well no stall throttle seems responsive and no flat spot which makes you shit it at a junction thinking its going to stall...

... How do you adjust the throttle cable?

Petes21st:

 

Removing the IAA valve is pretty simple really, just remove the batt first, ive done it twice now. When dismantling the valve, watch for the springs, i lost one of mine, now stuck at 2k RPM permanently grr, after a replacement now. Grrr

Its not the IAA giving me trouble bud, its the other ****er, the 'air regulator' it has two bolts and i cant get to the bottom one, or remove the pipe coming from the balance bar.

 

Stupid old pipe

oh yeah i wondered about that, how do you know that AR valve is cause, is there a way of testing the unit? I know with the IAA you just whack 12v to each solenoid and wait for the clicks.

 

I looked how to remove the AR valve, couldnt see any nut, just a hole where it looks like a nut should be, i suspect its been snapped off.

take of the centre cowl saying nissan and the two cables are there the one on the right loosentwo nuts on adjuster and pull any slack in the other one is the cruise control i think nowt important anyway... it just means not paly on cables give better responce and i found it got rid of my prob...if you turn on ignition but dont start car you can pull cable and hear a hiss do not tighten cable as far as the hiss make sure when you release the throttle body it stops hissing just !!

the problem im getting is basically a problem with a 'choke' not closing and not opening, the AR is the 'choke', my research has told me the little trap door inside needs a clean/grease.

 

And it seems im having another problem which i can only put down to the dump valves, but this problem only arisies when really warm so its hard to find.