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hey guys,

so hopefully this is the last time i have to put up a help question lol,

but my rb25det idles at 750-800, i cleaned out all the cold start and aac valve and tried to adjust the ilde again, i did all that and it came up with 750-800 once hot,

so alot of people think that is a good idle for the car (stock) but i find if i come to lights and brake a bit hard and put the clutch in at the same time the car will stall, so i like my idle between 900-1000 so it can catch it before it stalls,

now i know that you can adjust the idle from 0-250rpm on the ecu, but this is whats screws, my ecu doesnt have a light or a switch, it must have been taken out for some unknown reason,

so ive got 3 choices, unless there is another way?

Put a RB25det series 1 ECU in and run the car on that (if this can be done? heard something bout different fuel maps?)

Take the light and switch out of the series 1 ECU and solder it into the series 2 ecu? (if that can be done?)

Or get a series 2 ecu that has it so i can adjust this idle,

any comments would help me alot

(sorry if this is ment to go in general topics)

Cheers JV

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wind the screw out brings idle up, its out as far as possible,

ive got 1 more choice, tighten the accel cable to make it idle at 1000?

i know vct will be activated by doing this? but what does everyone think? it wont cause problems will it? or will the 20 deg advance with vct been on suck at idle?

hey ive had a think about this,

is there anyway that i can make the throttle body more open without activating the vct? like there is the screw (stopper) on the throttle body, so maybe if i screw it out so the throttle body will be more open? to bring the revs up. but the will this activate the vct? or does it get its signal throught the metal stopper? or can the tps be adjusted? and will this still mean my idles will go up?

Cheers hope this made sense

have u tried resetting your ecu?

and i think your base idle has to be set by taking one of the plugs off the aac valve then adjusting the screw

otherwise it doesnt do a great deal. not sure why but yeah. try reseting your ecu and pulling the purple plug i think off your aac valve then adjusting the screw

back when i bought my car it was dead stock, literally all it had was the spoiler, rear gtr pods and a stereo

it used to idle around 750 or so rpm when i got it and didnt stall, put an atmo bov on it for a little bit and it stalled so i took it off and it kept stalling every so often when returning to idle. Cleaned aac valve, cleaned afm did a few other things and nothing helped

reset ecu (unplugged battery and pressed brake down for 20 seconds or so) then car ran beautifully :thumbsup:

so yeh give it a go. As for the aac screw, if resetting the ecu doesnt help try what i said

hope you get it sorted

Edited by Boostin96
have u tried resetting your ecu?

and i think your base idle has to be set by taking one of the plugs off the aac valve then adjusting the screw

otherwise it doesnt do a great deal. not sure why but yeah. try reseting your ecu and pulling the purple plug i think off your aac valve then adjusting the screw

back when i bought my car it was dead stock, literally all it had was the spoiler, rear gtr pods and a stereo

it used to idle around 750 or so rpm when i got it and didnt stall, put an atmo bov on it for a little bit and it stalled so i took it off and it kept stalling every so often when returning to idle. Cleaned aac valve, cleaned afm did a few other things and nothing helped

reset ecu (unplugged battery and pressed brake down for 20 seconds or so) then car ran beautifully :thumbsup:

so yeh give it a go. As for the aac screw, if resetting the ecu doesnt help try what i said

hope you get it sorted

is that how u reset the ecu? i thought u just un plug the ecu and that will reset it? ok so maybe 2morrow i will wind the screw in and start the car, then once the car is warm unplug the aac and wind it out, and plug back in to see if it has brought up the idle, if not then i will give that ecu reset a shot,

what does your car idle at now? i still have all stock bov and stuff (going to block it off with a coke can cause it sounds like shit)

otherwise am i able to adjust that screw on the throttle body? so it holds it open more? but then how do i adjust the tps to match that? if any1 could give me info on that, then that would be good,

Thanks

answer 1 work whyyour stall cause it shouldnt

asnswer 2 adjusted the throltestop srew

alot of cars, well all of my cars (rb20 skyline, rb25 skyline, ca18det 180sx, sr20 180sx), when ever i have idled them on stock idle (800), if you are coming down a hill, and theres traffic lights which turn red, and you brake and put in the clutch quickly, the car wont be able to catch in time and stall,

so to counter this i bring up the idle so it can catch it in time,

for your answer number 2,

obviously i know i can adjust that, but if you have read my post i would like more info than that,

when throttle is open, the vct is on so timing is put up to 20deg instead of 15 deg, will this cause anything on idle?

also, if i was to do this to keep the vct off i would have to change the angle of the tps, so again, how do i know where its in the right position? what voltage does it put out in the right position? and what colour wires do i measure?

also i mentioned my ecu doesnt have something i can adjust idle with,

so really you havent answered anything,

ok guys, so i think i have fixed it,

i reset the ecu and put theidle screw back in to retry it again, cold start was idling at 1100 and then it went down to about 900 once a bit warm, as soon as the aac kicked in the car nearly stalled so i held the revs up so i could get this screw out a bit, got it out to the same place as before (right out) and the car was idling at about 750. so non of that fixed it,

so what i did is have my brother watch the revs and i screw out the stopper screw so it held the tb open a bit to bring the revs up, it took a few goes to get because if you went that 1/4 turn to far vct will come on and jump the revs up, so ive managed to adjust the idle up to 950 without vct coming on,

so im going to wait for it to cool and then start it up again and see how it goes, i probablyt should change the spark plugs to as its still got the spark plugs from japan lol, o well

cheers for all the replies

JV

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