Rough idle when cold engine
 

Hi guys,

quite recently i noticed that the idle isnt quite as it should be , when i start engine from cold it was really low, sounded like its gonna stall but it didnt , was just very low, normally when i was starting it from cold it was about 1100 and wheh warmed up 800 and it sounded as it should. so i asked few people and i was told to adjust the screw on the throttle body , i did to bring it up to 1100 when cold but then when it got warmed up it sounded really rough , so i stopped got out the car and turned the screw back a bit, got it back to 800 rpm and really nice and smooth idle. driven it for a bit and stopped for about 2 hours(engine wasnt exactly cold when i got back in ) and it was rough again - its not very bad , but its not what it should be .i check plenty of rough idle threads but havent really got propane torch to test it :( is there any other way to find out what it is? i got apexi power fc, can i use that to diagnose the problem ?

cheers

Have you worked through this page yet?

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/how-make-your-untuned-pfc-basemap-safer-idle-better-no-datalogit-needed-841706/

Just now thx I'll see if I can find solution there cheers

Its due to the temperature correction maps in your tune.

ok i went through this thread the only thing that i found that i could possibly do without wiping the tune (its been mapped by professionals and paid a lot of money for it so i didn't really want to erase that)was adjusting this air adjusting screw, took the elbow off turned it all the way in and then 1/2 out car sounded a bit rough when i turned it on but after like 10 mins it was pretty much normal apart from the slight wibration every now and then its basically going smooth and then ill have like a slight harder wibration that i can feel and then its normal again , its not very bad but its there and as far as i remember i always had that..

so i though everything is normal but didnt even think about it yesterday because engine warmed up during that time . so again today went to start it up from cold and omg, revs (on the commander) were jumping from like 500 to 900 very very quickly and car sounded like its gonna stall any second but it did not..

i opened the bonnet and twisted the screw at the throttle body (the one you can turn with your fingers) just turned it up to 1000 rev and it sounds fine but i know this is not a fix and when engine warm up ill have rough idle and will have to turn it down again :(((

any chance i can check what it is with commander? or adjust it without wiping everything ?


can i adjust this somehow ? without making my car die or making it worse?

right i've spoken to the garage where the car was mapped (they over 100 miles away so id rather avoid driving there untill i dont know what it is exactly) the reckon its something to to with some water valve below throttle body between tb and fire wall, apparently this could get stuck or something i was told to check this 1st , but kinda cant find it there, does anyone know what and where exactly it is?