can misfires at startup be from bad timing, fueling and or airflow during startup?
can misfires at startup be from bad timing, fueling and or airflow during startup?
By the prickle of my thumb something wicked this way comes!2008Chrysler 300c! 2013 heads/220/230 comp cam/LTheaders/FTI 2600 stall converter.
Misfires can come from a number of things but I mainly ignore startup misfires. After years of working for Chrysler and watching misfire monitors I have seen startup misfires on plenty of different vehicles. The worst ones for startup misfires were the 3.9/5.2/5.9 motors. The misfire monitors were so sensitive in the PCM. The misfire monitor in a Chrysler PCM watches for crankshaft deflection to determine if a misfire is present.Originally Posted by Turbo2gnx
Anything that can slow down the rotation of the crankshaft can cause an erroneous misfire or an actual cylinder misfire. Poor fuel quality, improperly adjusted ignition timing, improperly adjusted camshaft timing and improper throttle body settings can cause the PCM to detect a misfire even if it 8e erroneous or wn actual cylinder misfire they only occurs s couple of times during the startup process.
good morning. well ive noticed by changing the timing i see different amounts of misfire, so yes im seeing it somewhat the tune. wish i knew how to tune! i raised the timing from 15 max to get my torque back. when the tune was maxed with 30-40 my torque i had up to 120lbs now its down to only 68lbs. now im getting a lean issue and car is no longer drivable. going crazy!!! the tuner that i used is asking me to send him the tune that i did to get the firmer shifts and more torque that i have now. with his tune the most torque i got were 60lbs and a sloppy transmission! it was like the trans and motor were miles apart, now its way better! wish i knew what i was doin! how do i add more torque? when i give it more pedal the max tq is 120lbs and not feeling the PULL when i give it more and my downshift i cant feel.
By the prickle of my thumb something wicked this way comes!2008
now im getting a lean condition from only changing the min spark to jus a few degrees less than pt timing. how to make my WOT match my PT? and is there a site where it shows how to the grafts to show me what my engine is doing? i dont know how to populate the grafts to show the important info for adjusting the tune? things like hp, and the ones for VE tables. any help will be greatly appreciated!
By the prickle of my thumb something wicked this way comes!2008
Do you have a wideband installed?
Also, there are some vids available on YouTube that show how to set up the graphs in HP Tuners.
I learned a few things watching this video...maybe it can aid in your quest for more power!
https://youtu.be/8g_WZV5EguU
This one is about tuning VE...pretty decent video...
https://youtu.be/G7QGHuAYy48
yes i have a wideband, i dont think its working correctly.its mostly around 14-16, need to find a place to put it so i can view it while driving. i appreciate the links, im on my way to thme now, thanks.
By the prickle of my thumb something wicked this way comes!2008
i never had this many misfires! now its misfires while i drive....27 missfires on startup and while driving i see 200+ misfires? mostly on bank 1 and its pulling fuel on bank 1, no knock tho!
By the prickle of my thumb something wicked this way comes!2008
Pull the plugs again.
If in doubt, multiply everything by 1.1.
yes, im off tomorrow and planed on changing them but dont know which to get. i was told that the iridum was good and they fowled out quick so i tried the copper and its been runing lean.
By the prickle of my thumb something wicked this way comes!2008
the wideband bounce from 15.7 back to 14.4 fast at idle, it doesnt go below 14.5 while driving and getting on it a little.
By the prickle of my thumb something wicked this way comes!2008
ok today i changed the tune for the and tranny. with changing from 14.7 to 13.9 my misfires are 100% gone! not 1 misfire at startup nor while driving!
By the prickle of my thumb something wicked this way comes!2008
Do you know how many sensors are required to measure deflection?
Deflections @fast69mopar wrote about and you plagiarized lol
It is a PCM not a spintron machine
ket dropped a cyl or two
Ket, can you please explain ?Backfire? to me ?
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