alright so abit of info on my car to start... 1998 accord coupe with h23a vtec swap on stock trans.

lately when i go out in the morning it starts and stals right away unless i hold the gas to about 3k it does thos for about 3-4 minutes till it gets abit warmed up then runs flawlessly.. its started doing this about a week ago. when i hold the gas it lets out a puff of smoke that smells of rich exhaust. my iacv has been acting up for a while when i come to a stop it revs up and down for about a min then smooths out. yesterday i cleaned it hoping it would solve my problem yet it still acts up just not as much. no surprise this morningnit still had trouble starting... when it stalls it seems like the exhaust gets cloged or something it literally stops one shot not like a bog. kinda like i turned the ignition off.. all lights stay on in the dash so im thinking its not an ignition issue... could the iacv cause this? this really only happens in the morning when its cold out.

 

forgot to mention i have a catless exhaust

 

anyone ?

 

after the car is warmed up, when you pull the iacv connector while the car is running what does it idle at ?

 

idk i havnt done it when running ive unplugged it then started it up and it bounces like a **** from 600-800 really fast. ill try that tomorrow ill also try starting it up without it pluged in when itacts up to see what that does and let you know. thanks for the help

 

are you using an adapter plate for the iacv ?

 

no its straight on the intake

 

ok so i unplugged it and it idled at 5-600 but cant drive it with it unplugged anyway it kicks n jerks and dowsnt take part throttle jumps up and down

 

the next morning when its cold, test the two pin sensor under the distributor for ohms...should be 2500 ohms or so....then warm the car up completely and test it again, should be 200 ohms

wut ecu are you running ?

 

running a p13 right now but im waiting on a p06 vtec ecu chipped with a h23a street tune on it. i unplugged the iacv this morning when it was acting up and started it itstayed runing but with jumpy idle so it leads me to believe its the iacv. when testing the dizzy do you mean with the key in on position?

 

also coil and dizzy cap were replaced about 30k kms ago so i doubt its at fault, but ill test it anyway

 

well little update, this morning it started fine ran forabout 1 minute at 1500 as soon as it started warming up and idle settled to 1k it stalled and kept stalling till i held the throttle at 3 k for about a minute then ran fine again. i been driving it all day and except for idle jumping up and down at stop signs like usual from iac, its running flawlessly. this only happens after it sits all night... when it shut down i unplugged the iac and it kept stalling anyway... i didnt test the dizzy because it was too damn cold - 7c and i was in a hurry to leave. does this rule out the iacv as to causing my start and stall problem? itdoes seem to miss when itstalls and if i hold the gas at 2.5k i hear the occasional hickup/miss.. with the rich smelling exhaust i had a thought that it could be a sticking or leaky fuel injector that wakes up/unsticks after a while but that doesnt explain why it worked properly for a minute when idle was high because of the cold...

i really want to get this fixed before i move on with the project. i will be installing my chipped p06 tomorrow will see if that changes anything. damn iacv is 500$ here in canada so i would like to try ckeaning it once again and maybe bleed my cooling system before i dump 500 bucks into it.

 

no, i'm talking about the coolant temperature sensor for the ecu under the distributor

 

oh damn haha i didnt realize that a buddy of mine who is a mechanic told me its probably my tps causing the bouncy idle and start and stall in the morning now that i think of it its the only thing i didnt clean ill give that a try in the am and test the coolant sensor. could this maybe all caused by an air bubble in the system or the tps? im assuming its the one on the left next to coolant hose
i also have this thats unplugged under the vtec solenoide tho its never been plugged in. nore do i see a connector for it in the bay

 

well this morning shile changingmy clutch slave i decided to try testing that temp sensor while trying to get the connector off i almost ripped the thing out of the bung so im assumong thats the problem. anyway ill change that out and update

 

when you get the connector off, with the ignition off, spray that connector out real good with some electrical parts cleaner, both inside and outside where all that crud is, get it nice and clean

 

well replaced the temp sensor with a tested one from a f23 idle surge is still there ill update in the morning see if the start and stall is gone.. i adjusted the tps it was slightly off bit hat made no difference i recleaned the iac also. removed the throttle body and cleaned that up nice. cleaned the inside of the intake. if it still does it in the mornong ill film it and post a link

 

idle surging is always due to a vacuum leak, you need to find and fix the vacuum leak to cure the idle surge issue

 

 

as for the start and stall it hasnt stalled since i changed the ect it does give a little burble and rpm drop once or twice on coldstarts just doesnt stall so its 100% better

 

it doesn't sound like it was the conventional idle surge of going up and down, good to hear it appears fixed

 

yes completely fixed no more surging no more start and stall. but on another note i grenaded my cv axel yesterday when powershifting second woohooos -_- guess the tune made more power then i expected

 

Good call holmesnmanny,
What made you suspect the ect sensor? Just curious.

 

well someone on here told me to test it so when i went to test it i saw the conector was fucked... i changed it and my ecu at the same time it fixed my wonky idle fluctuation and my start and stall problem. yesterday i installed a 4 way button from a 2001 accord and it blew my flashers fuse. replaced it and everything was fine but nkt long afyer i started noticing the pop or stutter i was getting before and low and behold this morning the ****** started start and stalling again -_- im gonna try a new ect sensor tomorrow as the one i tried was a used one from a buddies f23 partout car. i hope its just that again and nota ecu problem.

 

Well it was good for all this time now thé oposite is happening runs great when cold as soon as its hot ans i give it sôme gas it dies out and sont stay running has trouble starting till its cooled off. im assuming m'y used ect gave out. Yesterday Wehile doing pulls it would start cutting out at High rpm this morning it juste died out ans wouldnt stay running till it cooled off and keeps doing that