o/t - 200sx idle hunting
Turbo Mini Forums

Got a weird problem with my 200sx.

When its up to temperature (or hot) if i take it out of gear or just come up to some lights/junction etc, the revs drop to about 500rpm (sounds like its about to stall) then rise to about 900rpm, then sometimes settles at 800 or fluctuates for a little while from about 500-900rpm. When its hunting if I blip the throttle to about 1500 it settles 90% of the time on 800rpm.

Only seems to do it when up to temp as i say, its idles really nicely at 1k when first started!!

I had the AFM off and cleaned it out with contact cleaner but it wasnt very dirty at all. The only other thing I can think of is perhaps the lambda sensor?

Am I right in thinking if I had a boost leak, it would stall completely and/or missfire? Same with coilpacks and plugs, surely id get some sort of missfire and bad running ie smoke of some sort but its fine in that respect.

Just wanted to see what you guys thought about it? Any ideas??

Thanks alot!!

Edited by richminiturbo. on 20th Dec, 2008.

i had a chavaleir years ago and it hunted at idle, i checked loads and it turned out to be dirt on the butterfly so restricting air at idle. when cold it had like a bypass valve so was alright

Check the idle air control valve bolted to the side of the pendulum

Take it off and give it a good clean. If that doesnt help, have a good search on www.sxoc.com

idle controll on them is ajsutable.(flat head machine screw on the idle valve) have a wee play with it if you dont find any vaccuum leaks :)

you dont have an apeci Power FC do you? there super fussy about the idle.

Edited by evolotion on 20th Dec, 2008.

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Cool thanks for the advice!!!

I serached on SXOC and theres quite a few threads about it, most people are saying AFM which ive checked, boost leaks and the idle control valve like you said.

I was going to ask which bits which on there but didnt want to get owned for being a noob lol.

t2clubby could you tell me if this is the idle control valve thats ive shown in the pic?



I was going to have it off earlier but ran out of light.

pull the plugs, theres a good chance the gap is too large re gap them to 0.030"


let us know how you get on

evolution - nah its completely stock electronic wise bar a turbo timer!

How would I go about finding a boost leak do you know? Hoping its not that! I've checked all the i/c joints bar the actual wing mount intercooler, which i think has hard pipes.

All the intercooler joints ive checked seem to be fine up top anyway hmmm.

Dumpvalve isnt leaking!

Steve, i'll try that then! The car has been stood for 2 years so I was expecting some teething problems, hope its not anything to do with the individual coilpacks, i didnt realise how expensive they are!!!

Edited by richminiturbo. on 20th Dec, 2008.

Edited by James_H on 20th Dec, 2008.

I need light James, I live out in the sticks and when its dark outside you tend not to see much believe it or not haha.

Will check the ICV 'moro, ill take it off and see if its cruddy, if i just played with it i guess the hunting will just be at higher/lower revs lol.

Just aswell get some new plugs aswell for good measure!

Edited by richminiturbo. on 20th Dec, 2008.

rich you dirty lil bugger!!! in ya 1st post you put


I was going to have it off earlier but ran out of light. lol

that aint a nissan problom teeeheee

i've had to do some of these chk, i've took off all the hoses that deal with boost & before reconnecting them i've put a light smear of RTV high temp sealant

one chk i've read to chk for leaks is spray the motor with wd40 if it runs smoother for a while under differing loads/speeds/rpms then ince the wd has dried/burnt away it go's bk to running a bit pants u have a leak somewhere, check all ya pipes & be super anal, sorry about using that word

SKYLINES ARE LIKE CLITS, EVERY FLANGE SEEMS TO HAVE ONE: see this sticker on my silvia

the Search-section on this forum is blummin superb & simple to use, unlike some other forums, without the search-section & the help of this bunch of chaps on here i'll never be able to !!!Start the day with a 998cc turbo!!! :) i'm getting closer though!

Tom Fenton says: I have it all, make me an offer

at idle your really only lookign for a vacuum leak on teh manifold, any wee slits in boost hoses or that only come into there own once you get up on boost :) so listen for hissing :) amd wiggle all the wee vaccuum hoses incase any have gone brittle :) chances are the idle valve just needs a clean and a wee tweak :)

turbo 16v k-series 11.9@118.9 :)

Denis O'Brien.

Noice one, i'll have a fiddle with my bits and let you know how I get on

That looks like it mate, hard to tell in the pic, plus im used to the sr20, hope you sort it mate, and take it easy on the roads, there have been too many write-offs this winter already lol

yep thats the idle solonoid pull it apart and give it a clean, also check the pipes leading upto it from the large hose onto the plenum.

oh and the service manual can be downloaded here http://www.h-dev.co.uk/index2.php?page=200sxmanuals

ello!!

Not had a chance to have a proper look at it yet, bloody christmas shopping is a right nightmare!!!

Tommy - I've tried downloading that service manual before but it gives me a "page load error" on firefox when I try to!

Dont suppose you could wire it too me via email or something could you? As i'd like to have a read of it!

email- jameshill_808@hotmail.com (if you dont mind of course!!)

Edited by richminiturbo. on 22nd Dec, 2008.

sorry rich i can't email it on my hotmail acount as its over 35MB and i can only attatch 10MB, unless somebody else knows how to?

i would sepperate you email addy enall rich otherwise, Spam AHOY!!

haha.....ass

Cheers for the new sig mate......

Edited by James_H on 22nd Dec, 2008.

Bollocks!!

Thats wrong, in 1995 i was 8 years old, you sick bastard!

woooooo im not sick! your the one that said it!

another link to the service manual if you've not found one, right click 'save as' then un-zip it.... http://bagpuss.swan.ac.uk/200sx/s13manual/...MANUAL%202a.zip


have you managed to sort the idle out yet?

Thanks tommy!! I managed to get a guy on SXOC to send them over msn to me so all sorted on the manual front, thanks alot anyway!

And yeah i've sorted the idle now, I changed the plugs over which made it run alot smoother, the ones that came out showed that the mixture was a tad rich.

I had the idle control valve off and it was aboslutely full of gunge, got some carb cleaner in there and left it in petrol over night, put it back on and set the idle speed after a long drive and now its idles an absolute treat!

Took the dump valve off, and it turns out this was causing the car to overfuel, evidence was on the plugs and from on the odd occasion having 3 foot flames spit out the back when letting off!!

Its runny really nicely now, need to get some coilovers on it asap, but think i'll need some new rear tyres first

Check out my cam cover now!!:

Hi,
Where's my shades??!
Nice finish on the paint though :)
Cheers,
Gavin :)

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Haha its alot brighter in real life! The camera on my phone didnt show it :(

Just gave myself a fright, was out ahem "playing" in the car, the massive bodge on my part (bottle top and jubilee clip replacing the dumpvalve) epically failed, even though its been fine for the last 4 odd days. So had a huge boost leak and it ran like a dog and eventually cut out. It was only a temporary bodge honest!

Thought id melted a piston or something!!

Edited by richminiturbo. on 4th Jan, 2009.