Abdullah

iTrader: (2)

today i begun tuning the idle of my car. the mods are in the signature. after turning the idle screw and unplugging the TPS and then keyying on the engine for 30 sec. then keyying off then plugging in the TPS and starting the car and repeating that many times the IAC position settled at 0!. i use hp tuners for tuning, here are the data from the VCM scanner :

TPS voltage = 0.82 v
TPS % = 1%
idle RPM = around 1000 RPM
IAC position = 0
IAC desired position = 0
fuel trim cell = 20

other info the might be helpful :

MAP = 54 to 55 KPA
MAF airflow = around 1.35 lb/min
MAF Hz = around 2950
all STFT and LTFT values were 0, i don't why? although the engine coolant temp was 194* F and that shows that the engine must be in the closed loop.

ECT = 194* F
IAT = 120* F

O2 voltage B1S1 = 447 to 451 mv
O2 voltage B2S1 = 443 to 447 to 451 mv
spark advance = 19.5* to 21*
knock retard = 0*

dynamic airflow = around 1.30 lb/min
idle desired airflow = 0.46 lb/min

inj PW Avg. B1 = 3.7 to 3.8 ms
inj PW Avg. B2 = 3.7 to 3.8 ms


for DTC's at idle :

[PCM] P0121 = TP sensor circuit insufficient activity (Old)(Current)(Immature)

[PCM] P0122 = throttle position (TP) sensor circuit low voltage (Immature)

[PCM] P0134 = HO2S insufficient activity bank 1 sensor 1 (SES)(Old)(History)(Current)(Immature)

[PCM] P0154 = HO2S insufficient activity bank 2 sensor 1 (SES)(Old)(History)(Current)(Immature)

[PCM] P0300 = engine missfire detected (Old)(Current)(Immature)

[PCM] P0405 = Exhaust Gas Recirculation (EGR) position sensor circuit low voltage (SES)(Pending)(Old)(History)(Current)(Immature)

[Restraints] U1000 = class 2 communication malfunction (History)(Immature)

[Restraints] U1016 = loss of class 2 communication with VCM (History)(Immature)

[HUD] U1000 = class 2 communication malfunction (History)(Immature)

all that info while the car in idle. why i get 0 counts for the IAC i thought after adjusting the IAC i would get 30 to 50 counts.

need help.

thanks

69LT1Bird

iTrader: (1)

You don't want it at zero, 20-30 for a stock cam or mild cam and 40-60 for a bigger cam.

Your TPS voltage is too high, should not be over .55 volts or PCM may send you into a different fueling cell.

The TPS postion should be 0%, not 1%.

Trim the locating tab off the TPS if you have to so you can get the voltage down, relearn the IAC again.

Abdullah

iTrader: (2)

what is the locating tab of the TPS? where it is? do you have pics?

thanks.

69LT1Bird

iTrader: (1)

Take the two screws out, you will see it. sometimes there is enough movement by just loosening the screws and rotating the TPS to correct a problem, if not, trim off the tab and see if that helps. In other cases you may need to slot out the holes a little bit in the TPS to get enough adjustment. It is very easy to do.

Full-Force

iTrader: (11)

There is a tab on the sensor that goes in a hole in the tb to keep it from rotating. You will need to remove the tab as well as elongate the holes in the sensor so you rotate it back to its original position of .55 volts or whereever it was. Then unplug the sensor and power on routine to reset it.

I had a problem with my car a while back where my tps was at 2%. I could reset it and it would still go back to 2% after I gave it gas. What I know is that if the tps is not zero then your iac will go to 0 which aint gonna work.

Abdullah

iTrader: (2)

thanks for the replies. i readjusted the TPS and i could get 0% TPS but still the TPS voltage is at 0.73 Volts with IAC counts of around 45.

still i didn't get the TPS value of 0.55 v?

i tried to elongate the hole in the TPS sensor but i'm not sure if i did it right and still i have a TPS of 0.73 V and IAC counts of around 45, what i have to do?

thanks.

Abdullah

iTrader: (2)

btw the tap is on the throttle body not in the TPS sensor, the TPS sensor has a hole in it that the TB tap gets in. my throttle body is 90mm NW with Fast 90mm. my car is 2000 LS1 camaro.

Full-Force

iTrader: (11)

A stock sensor on an LS1 has the tab on the sensor itself.

You should be able to elongate the holes enough to rotate the sensor back far enough to get it back to .55.

I have had to elongate the holes amost to the point that i cut the hole out on one end.