Struggles to start when warm
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Struggles to start when warm *mods are in sig*
So I have an odd issue. When the car is cold, it fires up right away. I'm talking like 1.5 seconds of cranking and we're good.
When the car is warm, it takes a bunch of cranking, and typically me giving it some gas to get it to turn over. And even then, despite me stepping on the pedal, its extremely lazy when starting (tach jumps to about 400, hesitates there, then lazily climbs to idle around 850-900).
When I brought this up to my tuner, he sort of just shrugged at me and said "IAC counts are showing full, I unno" and that was basically that.
I unfortunately don't have HPTuners yet, so I can't post my file (sorry) but I was wondering if anyone thought this was anywhere close to normal? Or if anyone has experienced this and if so, what's a good fix?
I haven't replaced the IAC, since it seems to work normally the rest of the time.
So I have an odd issue. When the car is cold, it fires up right away. I'm talking like 1.5 seconds of cranking and we're good.
When the car is warm, it takes a bunch of cranking, and typically me giving it some gas to get it to turn over. And even then, despite me stepping on the pedal, its extremely lazy when starting (tach jumps to about 400, hesitates there, then lazily climbs to idle around 850-900).
When I brought this up to my tuner, he sort of just shrugged at me and said "IAC counts are showing full, I unno" and that was basically that.
I unfortunately don't have HPTuners yet, so I can't post my file (sorry) but I was wondering if anyone thought this was anywhere close to normal? Or if anyone has experienced this and if so, what's a good fix?
I haven't replaced the IAC, since it seems to work normally the rest of the time.
TECH Fanatic
Joined: Dec 2017
Posts: 1,467
Likes: 265
From: Bossier City, Louisiana
Ask your tuner for a copy of your file - you paid the credits for it and its licensed to your vehicle. Additionally, see if he can gather some logged time using "HP Tuners" (or whatever other tool) while your engine is running from inside your PCM while your engine is suffering this problem. Post both files here and maybe somebody (not me) can offer some advice.
I like to keep a copy of my vehicle PCM operating system as a backup because nobody else can easily help you without this file to possibly put into a spare PCM.
Rick
I like to keep a copy of my vehicle PCM operating system as a backup because nobody else can easily help you without this file to possibly put into a spare PCM.
Rick
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Thanks. I'll get in touch with my tuner. unfortunately I moved about a month after the car was tuned, so I can't take it back to him for any logging (one of the reasons I'm getting HPTuners and wanting to get into tuning myself) but I'll see if I can get something going.
Launching!
Joined: Jan 2018
Posts: 283
Likes: 0
if applying throttle at warm crank helps its either starved for air or pig rich. given it starts cold fine I would think its not a lack of air.
if spraying some starting fluid into the intake post MAF and air filter helps more than applying peddle I would say its lean and needs more cranking fuel.
it should start warm fine with 8-10 degrees timing on crank.
start up airflow, cranking VE, cranking FA mult fuel, startup flare control, startup underspeed time, idle timing, ECT spark corrections, catalyst heating spark corrections, AFR spark corrections are areas you can investigate.
if spraying some starting fluid into the intake post MAF and air filter helps more than applying peddle I would say its lean and needs more cranking fuel.
it should start warm fine with 8-10 degrees timing on crank.
start up airflow, cranking VE, cranking FA mult fuel, startup flare control, startup underspeed time, idle timing, ECT spark corrections, catalyst heating spark corrections, AFR spark corrections are areas you can investigate.
Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
Well it took a long time, but I finally managed to get my hands on the tune file.
I'm very new to tuning, so I'm not sure exactly what looks good and what doesn't in terms of the fueling histograms. I am using 42# injectors for reference.
I'm thinking it's a fuel thing, since as soon as I hit flood clear levels on the gas pedal (looks like 80% throttle) it fires right up.
I just got hpt today so I'll see if I can get some logs over the next few days.
Thanks for all the help!
I'm very new to tuning, so I'm not sure exactly what looks good and what doesn't in terms of the fueling histograms. I am using 42# injectors for reference.
I'm thinking it's a fuel thing, since as soon as I hit flood clear levels on the gas pedal (looks like 80% throttle) it fires right up.
I just got hpt today so I'll see if I can get some logs over the next few days.
Thanks for all the help!
Last edited by HappySalesman; Sep 13, 2018 at 12:11 AM.
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Verdad Gallardo Thread Starter
Joined: Jun 2014
Posts: 1,241
Likes: 47
From: Noblesville, IN
As for racing, I don't do a whole lot. This car is 100% street, and will probably never see a track lol. I am looking in the next year or two to get a hardtop and converting that into a street/strip car, with emphasis on the 'strip' portion
I thought it might be a leaky injector, but figured the easiest thing would be to look at the tune first and then start pulling parts. It's done it since day 1, and the injectors I purchased were cleaned and tested right before I bought them.
Launching!
Joined: Jan 2018
Posts: 283
Likes: 0
try to work out if it wants more or less fuel for hot start. crude way is apply throttle on crank. if that helps it wants more air or less fuel.
if it doesn't or it makes it worse it wants more fuel for warm crank and start.
use
cranking spark
start up airflow
cranking fuel
cranking VE
startup underspeed time delay
as starting point to edit
if it doesn't or it makes it worse it wants more fuel for warm crank and start.
use
cranking spark
start up airflow
cranking fuel
cranking VE
startup underspeed time delay
as starting point to edit