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ok here the part where i have a cry.

was out last weekend with the sau qld crew and wile driving down a bumpy track one of my cooler pipes got ripped off, the car spluttered as usual(ive popped pipes before) and died after a few seconds. we got it all on again and everything was fine until a few days ago i noticed a problem.

when i turn the car on (its an auto btw) it used to start up then go to about 1500revs for a bit

till oil was circulating fine then drop to just under 1000 where it usually idled,

but now it starts up (now needs a foot on the throttle or it just dies)

then wen i take my foot off the throttle it goes straight down to 800revs and stays put

-therefore car not warming properly.

also wen i put my foot down to drop a gear as its auto it drops down fine but if i lift off the gas completly the revs drop to idle revs, not to the gear aboves rev range.

i have been told may be boost/vac prob or afm or aac valve prob, how can i check these? i have a vac+boost guage in the car and they read as normal so would there be another problem?

ps the cooler piping coming off mite not have been the culprit, i also did some quite harsh mountain driving that day, nothing i havent done b4 tho. any ideas? help is much appreciated.

dazza

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I thought normal idle was 700rpm for a Skyline anyway.. Maybe your car was broke before and now you've fixed it? Hehe.

My car sometimes used to almost die after first starting the car, this was fixed after I replaced the o2 sensor and the fuel filter though (replaced at same time, so not sure which one actually fixed it - most likely fuel filter I'd say).

easy peasy mate. Make as adapter up and pressurize your intake system, 10 to 15psi should do it. Will show up any intake leak. The pipe or hose is probably still leaking or damge may have been caused elsewhere on that intercooler pipe.

Mike

well yea wen its warm, in an auto the revs are lifted to warm the engine up and get the oil up and round the engine,

what im saying it idles at nomal temp even wen cold then after being reved, idle so low to the point it nearly cuts out

easy peasy mate. Make as adapter up and pressurize your intake system, 10 to 15psi should do it. Will show up any intake leak. The pipe or hose is probably still leaking or damge may have been caused elsewhere on that intercooler pipe.

Mike

all my sh*t would blow if i went that high, the car runs on the stock 7psi and stuff was blowing then

ive checked and rechecked the pipes and there fine so i dunno whats the prob with the idle

all my sh*t would blow if i went that high, the car runs on the stock 7psi and stuff was blowing then

ive checked and rechecked the pipes and there fine so i dunno whats the prob with the idle

Lol, he didn't explain himself too well.. think he means leave the car turned off and run pressure with an aircompressor into the intake with a pedal on accelerator pedal (to open the intake). He doesn't mean up the boost.

Manual Skylines also idle higher when cold, not just autos. Mine idles at about 1,500rpm then drops down to 700rpms, which is factory spec I believe.

It's gonna be 'the first air control valve' located underneath the intake manifold and has hoses running off it up to the aac valve. They get stuck open in the one position allowing a vacuum leak to upset the idle.

I'm having the same problem at the moment funnily enough after blowing an intercooler pipe off. A part time solution for me was too block off the this valve, although it makes the car run a bit rich at idle, you just have to adjust the screw on the aac valve until it revs happily. I'm looking for a replacement one but they're not the most common thing to come across.

If you want to test my theory get some long nose pliers and block the front hose that goes from facv to aac.

hmmm yea well there is a prob, the pipes come loose very easy you see-i dodged up the install, hence y in my sig im asking for a piping kit.

the bottom pipe scrapes on my drive everyday and then wen i boost to 7 with no lips on the pipes they pretty much fall off.

nehow-its def boost problem, only getting 5psi out on full throttle so i figure its either a dud pipe of blown hose off sumwhere,guna fix it on the weekend so yea i *hope* problem solved, thanks for the insight tho.

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