aperson

stock KA24DE (auto to manual conversion)
white smoke from exhaust when idling or stopped
the smoke doesn't smell sweet, it smells...bad
no milky oil on dipstick or oil cap
coolant is clean, not loosing any
never overheated- temp is rock solid in the middle always
WTF?

idle would surge after shifting into neutral (1500 for a few secs, then back to 900) other wise idle was rock solid at 800-900 rpm
as per my search i started by cleaning the MAF with MAF cleaner first

now my idle is hunting 1500-2000 when i blip the throttle and more white smoke.
WTF?

my next trick is to investigate IACV, coolant temp sensor and TPS...

I'm kinda new and worried I'm totally missing something obvious here guys.
Any Sage wisdom would be greatly appreciated

apex128

My car does the same thing! I have a dual cam s14 ka-t, and suspected the turbo for a while, but I don't see how that is possible as I've redone the drain and put a restrictor in the feed as well as rebuilding the turbo with all new seals.
I'm thinking maybe pinhole leak in the HG, but again, no coolant loss.

I think we might just have old rings or it is going rich for a second because of the automatic ecu.
How many miles on your KA?

aperson

My ka has 264k kms, about 165k miles
Maybe A pin hole hg leak is all it takes?
lets keep updating if either of us make progress

aperson

pulled codes from ECU
code 12 is the only one (MAFs)

with warm engine running i unplugged the MAF, the idle went up and held steady, plugged back in and idle went down and got rough again.

I ordered a new MAF, as cleaning this one only made it worse.

Can a failing MAF cause poor mpg?
Can a failing MAF cause white smoke?

Will update

Gearhead9992

Yeah it can cause poor mpg if the ecu doesnt get the right readings from the maf then it could just dump fuel to prevent a lean condition

burnsauto

can you elaborate a little bit more, "bad" doesn't help much as far as a smell. Have you done a leak down test? I know you said it's white, but the valve seals may be leaking, hence the smoke when it sits and at idle, and when you blip the throttle. Not saying the keyboard mechanic way of fixing things is always correct, but it may be something to look into, especially on an old motor where rubber seals love to wear out.

__________________

lunchmeat

Mine did something similar. Only smoked at idle and smelled of gas. I cleaned the throttle body and maf, replaced both temp sensors(gauge one was bad anyway), and it still did it. Replaced the injector orings and no more smoke.

Sent from my HTC One using Tapatalk