Fresh Ls1 Build Cammed Stalled Idle Tuning Help
02-23-2015, 10:06 PM
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Fresh Ls1 Build Cammed Stalled Idle Tuning Help brief overview of engine
mild ported 243 heads
new rebuilt block 99 ls1
ls6 intake
ported maf ends 4" cold air intake
ported stock trottle body
42lb injectors
3600 stalll shift kit etc
long tubes
EPS Cam 228/23- .600/.600 112
ok so still having idle issues
it idles but once it drops it starts to backfire due to rich or lean im not sure then I just shut engine off in fear of hurting engine
Iac hover around 140ish to 200 even at operating temp
I tired adjusting throttle blade screw and zeroing out the TPS I even tried drilling throttle blade out just seems like I cant lower my iac counts to get a stable idle
I would really like some help with this been going at this for like a month here and there
I changed out coils and spark plug wires all sensors are new but haven't replace any I installed cam dot to dot
Im sure im missing out important info
to keep it from backfiring I have to gas it
if i let car run once it gets up to temp it starts to backfire then eventually dies
I did a short drive around block but just don't feel likes it ready to take a drive to get a good datalog
it backfires really loud from exhaust
here is my logs
22feb20148.hpl drove around the block with this log
22feb20146.hpl these log are in park
22feb20145.hpl
will try to drive and get a longer data log with this tune
mild ported 243 heads
new rebuilt block 99 ls1
ls6 intake
ported maf ends 4" cold air intake
ported stock trottle body
42lb injectors
3600 stalll shift kit etc
long tubes
EPS Cam 228/23- .600/.600 112
ok so still having idle issues
it idles but once it drops it starts to backfire due to rich or lean im not sure then I just shut engine off in fear of hurting engine
Iac hover around 140ish to 200 even at operating temp
I tired adjusting throttle blade screw and zeroing out the TPS I even tried drilling throttle blade out just seems like I cant lower my iac counts to get a stable idle
I would really like some help with this been going at this for like a month here and there
I changed out coils and spark plug wires all sensors are new but haven't replace any I installed cam dot to dot
Im sure im missing out important info
to keep it from backfiring I have to gas it
if i let car run once it gets up to temp it starts to backfire then eventually dies
I did a short drive around block but just don't feel likes it ready to take a drive to get a good datalog
it backfires really loud from exhaust
here is my logs
22feb20148.hpl drove around the block with this log
22feb20146.hpl these log are in park
22feb20145.hpl
will try to drive and get a longer data log with this tune
Last edited by zachary3; 02-23-2015 at 10:09 PM. Reason: update title
02-23-2015, 10:25 PM
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Your TB voltage is too high. .8V is too much. Need to close your TB screw back down to around .6 or so. Then try to get your IAC counts down. I'm sure the tune needs adjusted as well to keep from backfiring. Hard to tell in your logs since you have to keep revving it to prevent it from dying...
02-23-2015, 10:37 PM
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Your TB voltage is too high. .8V is too much. Need to close your TB screw back down to around .6 or so. Then try to get your IAC counts down. I'm sure the tune needs adjusted as well to keep from backfiring. Hard to tell in your logs since you have to keep revving it to prevent it from dying...
how else can I get the IAC count down?
I tried adjusting the TB volt but its too high now and then I drilled the throttle body and that's where I got today
im going to lower the the TB volts back down
and I do have to revv to keep it from dying to atleast try to get a datalog session in atleast
I was opening TB 2% at a time and resetting TPS to see if it would stabilize the idle
02-23-2015, 10:46 PM
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When the PCM reads a TPS voltage over .5V it thinks you have your foot on the throttle and it therefore switches out of idle mode. (Maybe its 0.6V, but 0.8 is too high.)
Which 42lb injectors do you have? Did you find complete tuning tables for them, including the Short Pulse Adder?
Which 42lb injectors do you have? Did you find complete tuning tables for them, including the Short Pulse Adder?
02-23-2015, 11:32 PM
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yes I got them from FIC and they sent the tune data for them
yea I will adjust TB back I had screw bottom out and .5 ish
my only goal going above .6 was to see if idle would improve
yea I will adjust TB back I had screw bottom out and .5 ish
my only goal going above .6 was to see if idle would improve