idle issues with a twist

[andrew600]

s13 blktop, 91 car, hks ssqv bov not recirc. dont tell me its the bov because its not open at idle.

it only happens when its colder than 55-60*
anything above it runs perfect and idles perfect, i bought it at the beggining of spring so i never had any cold days like we are getting now.
but mornings the cars runs rough and idles rough and if it gets warmer through the day it will idle better, yesterday was cold all day so it wouldnt idle well at all. saturday however was almost 70* and it ran perfect all day long.

[ch1873857]

fuel pressure.

[96Turbo]

coolant temp sensor? clean MAF?

[Chaluska]

coolant temp sensor?

thats my guess... it is supposed to idle higher when its colder out, to warm up the engine quicker.. either intake air temp sensor, or coolant sensor..

[andrew600]

my coolant temp is displayed in the dummy gauge if that matters. i have been smelling fuel lately. but from the back, the o ring that fits on the gas tank may need to be adjusted.

ill look into all of these and report back, thanks so much guys!

[Shift n Drift]

m night shamalon

[andrew600]

oh cool story bro.

[ch1873857]

my coolant temp is displayed in the dummy gauge if that matters. i have been smelling fuel lately. but from the back, the o ring that fits on the gas tank may need to be adjusted.

ill look into all of these and report back, thanks so much guys!

ok so i have money on it being a fuel pressure issue. i had the exact same problem. however you need to figure out whats causing it. the fuel tank o ring isnt going to cause this.

the dummy gauge runs off a DIFFERENT sensor than what your ecu reads ( the one that matters. its gonna be the bigger of the two sensors going into your water neck. the small single wire sensor is for the gauge. make sure its the correct one for your ecu and not a KA one unless they are interchangeable.

what is your fuel setup like? if you have a walbro 255lph fuel pump on a stock fuel pressure regulator this will throw off fuel pressure and make it run really rich. when it gets cold, even richer. if you have an afpr do you have a method of monitoring fuel pressure? look in the FSM for proper specs.

i had this problem back when i was 16 and stupid and built my CA18. i learned a lot from my own mistakes and this was one of them. i did right by running a nismo fpr with the walbro and fp gauge however unknowingly tapped into the return and was reading return pressure. needless to say i had fuel pressure cranked up to probably 65-70psi. idk probably not that high but you get the point. hope this helps. its a golden rule though. always run an adjustable fpr with a walbro.

[andrew600]

I have walbro on idk what fpr. I will look onto what you said. Nismo fpr is a good sub for what I have?

[280zx2by2]

my coolant temp is displayed in the dummy gauge if that matters.

I loled. :keke:

[ch1873857]

if you didnt change the fpr most likely its stock. nismo is a direct replacement but you will need a way to monitor fuel pressure once adjusted at least long enough to set it.

[andrew600]

fixed!
it was iacv, and cough cough.....bov was leaking....

[ILoveJDM]

cough dat cash money up ch1873857

[iSlide240]

idle air temp sensor ?

[andrew600]

cough dat cash money up ch1873857
:picardfp: lol


idle air temp sensor ?
the little doohicky in between my intake.
http://img51.imageshack.us/img51/2894/dsc2585r.jpg (http://imageshack.us/photo/my-images/51/dsc2585r.jpg/)