Sputtering During Warm-up
#481
#484
New Member
iTrader: (5)
just how i suspected. it's the ECU causing the problem. I was getting the sputtering problem just about every single time i started the car. and didn't let it get warm. yesterday I decided to Hook up Cipher and let the ECU do the target A/F relearn. no more sputtering as of yesterday. I'll keep you guys updated to see if it slowly comes back. but i think it might be something with the cold start / fuel enrichment program.
#486
resetting instructions . . .
http://www.technosquareinc.com/350reset.htm
haven't been able to do it myself . . . definitely need a stopwatch . . good luck
CIPHER is a data logging proprietary cable/program from Uprev that connects to your OBD2 port and can read / write values to the ECU
http://uprev.com/products.php#product_cipher
http://www.technosquareinc.com/350reset.htm
haven't been able to do it myself . . . definitely need a stopwatch . . good luck
CIPHER is a data logging proprietary cable/program from Uprev that connects to your OBD2 port and can read / write values to the ECU
http://uprev.com/products.php#product_cipher
#488
#489
Also about the ecu reset . . . what if the Z is not stock . . ? ? usual intake, cats, exhaust . . etc . . ??
im considering buying a CIPHER myself, itll be great if someone can confirm that CIPHER a/f ratio relearn can fix the issue . . . .
#490
New Member
iTrader: (5)
you waiting on header gaskets ? ?
Also about the ecu reset . . . what if the Z is not stock . . ? ? usual intake, cats, exhaust . . etc . . ??
im considering buying a CIPHER myself, itll be great if someone can confirm that CIPHER a/f ratio relearn can fix the issue . . . .
Also about the ecu reset . . . what if the Z is not stock . . ? ? usual intake, cats, exhaust . . etc . . ??
im considering buying a CIPHER myself, itll be great if someone can confirm that CIPHER a/f ratio relearn can fix the issue . . . .
#491
Just an FYI, I never heard of this issue on the G35 sedan's (HR). It seems only the Z's have them, which would mean it's not a mechanical issue but software. Has anyone tried using Uprev to tune the cold starts? I don't know if its even possible :/
#494
Registered User
Join Date: May 2010
Location: Fayetteville, NC
Posts: 1
Likes: 0
Received 0 Likes
on
0 Posts
I think it might be a combination of the ECU's Cold enrichment and a faulty sensor. Mine will sputter and carry on 2 min after i start the engine and begins to warm up and then run normally 30 sec. to 1 min after that, however the engine will always perform what feels like a timing retard at 1800 rpm regardless of how long that its been running. There is no "rev-limiter" effect as when its warming up but it will bog for a split second and then continue running normally. This happens any time there is no to very little load on the engine. I performed a full ECU reset with all the corresponding sensor relearning tasks, and still no change to either problem. I was reading the service manual the other day and happened to stumble upon something in the ECU called 'No Load Fuel Cut' that basically said that when the engine operates over 1800 rpm, that after a certain time it would cut fuel until it engine speed fell below 1500rpm. While i dont think this might be the problem because those that watch the AFR have said nothing is out of normal, it may be conflicting with another program/map in the ECU based on bad info from a bad sensor. Just throwing this out there as it may be a step in the right direction or at a minimum its a little more info than we might have had.
#495
#497
I agree it can't be only an ECM issue, as a brand new car don't sputter...
I was able to check the front O2 sensor and Short Fuel Trim datas during sputtering, they became crazy, up and down... I guess that the ECM try to correct datas which are wrong, but from wich sensor(s)
I was able to check the front O2 sensor and Short Fuel Trim datas during sputtering, they became crazy, up and down... I guess that the ECM try to correct datas which are wrong, but from wich sensor(s)
#498
New Member
iTrader: (5)
I agree it can't be only an ECM issue, as a brand new car don't sputter...
I was able to check the front O2 sensor and Short Fuel Trim datas during sputtering, they became crazy, up and down... I guess that the ECM try to correct datas which are wrong, but from wich sensor(s)
I was able to check the front O2 sensor and Short Fuel Trim datas during sputtering, they became crazy, up and down... I guess that the ECM try to correct datas which are wrong, but from wich sensor(s)
#499
#500
fawk . . tonite i got my first code while sputtering: P0300 random multiple cylinder misfire detected. Got it while revving aroudn 3k~4k range while sputtering. This is actually damaging the engine in the process. From now on Im gonna warm up the engine @ idle for 10 mins before taking off.