Need Help w/Engine Tune - HPTuners
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From: Beaumont, TX USA
Need Help w/Engine Tune - HPTuners I have HPTuners, a 2002 Camaro Z28 with TCI3500, Transgo Shift Kit, Hooker LT’s, Custom Y-pipe, SLP Cold Air Kit & MAF, ASP Pulleys, 180 Thermostat, and 3.73 gears. Basically an almost full bolt-on car.
Can someone please take a look at this log and help me out? The log is from driving around town a bit and then a little cruising on the Interstate. Need to know which way to go. Looks like the LTFT’s start out ok then go bad… maybe. Not sure. Does it look like I am running rich after the headers? What else should I be looking at?
02Cam-061504 Log
Thanks for the help in advance.
Can someone please take a look at this log and help me out? The log is from driving around town a bit and then a little cruising on the Interstate. Need to know which way to go. Looks like the LTFT’s start out ok then go bad… maybe. Not sure. Does it look like I am running rich after the headers? What else should I be looking at?
02Cam-061504 Log
Thanks for the help in advance.
You have no TPS above 47% so the log tells
nothing about WOT fueling. It appears that
you are closed-loop the whole time. The
higher-MAP FTCs show positive LTFTs which
will perturb your WOT tune but this is really
saying that your base (untrimmed) tune is lean.
What's really funny is, you have positive LTFTs
being counterbalanced by ~ equal, opposite
STFTs (see about line 1400-1420) and making
the closed-loop O2s "properly jiggy" and the
mixture basically neutral. I think this indicates
some "history effect", my suspicion is header
thermal effects on the O2s, that give you
some false-lean (+LTFT) impulse when cool that
gets short-term corrected (-STFT) when hot.
The loop is trying hard, it seems to be working,
and the trims are not that far out of bed - I
don't think it's an intrinsic metering error but a
feedback (O2 temperature) error that's messing
the trims around (sum of trims at midband being
a slight negative, indicates metering is relatively
true).
Set your fans lower. No reason your ECT should
swing over the 194F 'stat crackpoint by more than
a couple of degrees. Try FAN1 on=191, off=190
and FAN2 on=196, off=195. Or something like.
Look into a decent cold air induction setup. The
IATs are swinging up into areas where you will
start to pull spark.
nothing about WOT fueling. It appears that
you are closed-loop the whole time. The
higher-MAP FTCs show positive LTFTs which
will perturb your WOT tune but this is really
saying that your base (untrimmed) tune is lean.
What's really funny is, you have positive LTFTs
being counterbalanced by ~ equal, opposite
STFTs (see about line 1400-1420) and making
the closed-loop O2s "properly jiggy" and the
mixture basically neutral. I think this indicates
some "history effect", my suspicion is header
thermal effects on the O2s, that give you
some false-lean (+LTFT) impulse when cool that
gets short-term corrected (-STFT) when hot.
The loop is trying hard, it seems to be working,
and the trims are not that far out of bed - I
don't think it's an intrinsic metering error but a
feedback (O2 temperature) error that's messing
the trims around (sum of trims at midband being
a slight negative, indicates metering is relatively
true).
Set your fans lower. No reason your ECT should
swing over the 194F 'stat crackpoint by more than
a couple of degrees. Try FAN1 on=191, off=190
and FAN2 on=196, off=195. Or something like.
Look into a decent cold air induction setup. The
IATs are swinging up into areas where you will
start to pull spark.
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False O2 readings are not going to cause the PCM to think it is in PE mode and using cell 22 when the engine is idle or low RPMs.
If the O2s were that far off then it would be tripping DTC error codes
Sort that Excel sheet by MPH and you see even at idle with engine temps in the 190 plus degrees PCM is using cold idle cell 20 and cell 18 A/C ON idle ( was A/C on at times ?)
If it was not on then if there is custom CAM then it has lost vaccum at low end and requires the PCM to be tuned for that CAM.
I'd monitor MAP and engine vaccum and see if they look normal or not.
Being at one time both LTFT and STFTs are reporting -100 rich I would suspect,
intake or exhaust leak right side, MAF, unmetered airflow, leaking O ring ( bottom side of injector)
If the O2s were that far off then it would be tripping DTC error codes
Sort that Excel sheet by MPH and you see even at idle with engine temps in the 190 plus degrees PCM is using cold idle cell 20 and cell 18 A/C ON idle ( was A/C on at times ?)
If it was not on then if there is custom CAM then it has lost vaccum at low end and requires the PCM to be tuned for that CAM.
I'd monitor MAP and engine vaccum and see if they look normal or not.
Being at one time both LTFT and STFTs are reporting -100 rich I would suspect,
intake or exhaust leak right side, MAF, unmetered airflow, leaking O ring ( bottom side of injector)
Last edited by Team ZR-1; Jun 16, 2004 at 12:17 PM.
Thread Starter
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From: Beaumont, TX USA
Its been raining here so no WOT runs or anything, streets too slick. A/C was on then turned it off when I saw it on. I replaced the O2 sensors last weekend. It has not thrown any codes at all, no SES light. Cam and engine internals are all stock. All the SLP stuff was on the car when I bought it, gonna try to go with something else soon as I can. I lowered the fan temps and will log some today now that it’s a little sunny out. If yall don’t mind, maybe take a look at it for me. I’m new to all this, I’m used to the old carb’ed engines so I really do appreciate the help.
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Wish I could. I bought the car used and it had all the aftermarket SLP stuff on it, dont have the original parts or MAF. Here is a log from this evening. With a WOT run at the end. Heading to the Dyno to play this weekend, any suggestions would be great.
02Cam-061604 Log
Thanks again for all the help, really appreciate it.
02Cam-061604 Log
Thanks again for all the help, really appreciate it.
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Originally Posted by ataylors
I would look long and hard at why your trims are off from one side to the other. There has to be some kinda leak or possiable faulty injector.
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From: sojourning....looking for my city whose builder and maker is God.
Originally Posted by SebastianLopezJr
I have HPTuners, a 2002 Camaro Z28 with TCI3500, Transgo Shift Kit, Hooker LT’s, Custom Y-pipe, SLP Cold Air Kit & MAF, ASP Pulleys, 180 Thermostat, and 3.73 gears. Basically an almost full bolt-on car.
Can someone please take a look at this log and help me out? The log is from driving around town a bit and then a little cruising on the Interstate. Need to know which way to go. Looks like the LTFT’s start out ok then go bad… maybe. Not sure. Does it look like I am running rich after the headers? What else should I be looking at?
02Cam-061504 Log
Thanks for the help in advance.
Can someone please take a look at this log and help me out? The log is from driving around town a bit and then a little cruising on the Interstate. Need to know which way to go. Looks like the LTFT’s start out ok then go bad… maybe. Not sure. Does it look like I am running rich after the headers? What else should I be looking at?
02Cam-061504 Log
Thanks for the help in advance.
Sorry, it would not let me upload it.
Thanks. I'm gonna get under the car and take a look at everything tomorrow after work. I was wondering what could or would make the trims off.
A lot of cars have a bank-bank imbalance.
Being off by 4 or more is maybe a little on
the outside but if you don't find a vacuum
leak then it's likely fuel and exhaust symmetry
(backpressure / scavenging and sensor
location / response) differences.
My two sides are hardly ever equal but only
differ by about 1 or so - stock exhaust and
untouched intake plumbing.
Being off by 4 or more is maybe a little on
the outside but if you don't find a vacuum
leak then it's likely fuel and exhaust symmetry
(backpressure / scavenging and sensor
location / response) differences.
My two sides are hardly ever equal but only
differ by about 1 or so - stock exhaust and
untouched intake plumbing.
Thread Starter
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From: Beaumont, TX USA
Originally Posted by jimmyblue
A lot of cars have a bank-bank imbalance.
Being off by 4 or more is maybe a little on
the outside but if you don't find a vacuum
leak then it's likely fuel and exhaust symmetry
(backpressure / scavenging and sensor
location / response) differences.
My two sides are hardly ever equal but only
differ by about 1 or so - stock exhaust and
untouched intake plumbing.
Being off by 4 or more is maybe a little on
the outside but if you don't find a vacuum
leak then it's likely fuel and exhaust symmetry
(backpressure / scavenging and sensor
location / response) differences.
My two sides are hardly ever equal but only
differ by about 1 or so - stock exhaust and
untouched intake plumbing.
Gonna go over car this afternoon, check under for exhaust leaks and over for vacuum leaks. Intake never been off car, only thing close to that is the AIR system has been removed.
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From: Beaumont, TX USA
Originally Posted by ataylors
the MAF wont make it out of balance. There has to be something on one side affecting it. How do you know the intake has not been off?
