IAC on turbo v8 Help needed

[vp304]

found the bit in tuner pro showing the faults in red.
Weather has been crap here. Hopefully tomorow weather is beter and i will strip back the extended bits of the iac and tps loom and check them out

[vp304]

back. Checked all my wiring was all good but resoldered and heatshrunk the lot.
Drove the car let it warm up and it still shows iac and tps stuck faults ??? i dont know why
Might change the iac tomorow to a spare i have as its now showing 130 steps all the time. Dont know why as it was working perfect before na and the car was only of tthe road for 3 weeks during the conversion.

[VL400]

Code 35 gets set when the IAC cannot keep the RPM under control, it has a desired idle RPM and tries to keep it as close as it can to that. Clear the fault codes and the RAM by removing the battery and then take another log, can then see where the error is getting set and all the learned idle stuff has been cleared. Have a look at the desired idle, the current RPM and your IAC position.

Code 46 is when the ECU detects vacuum and low voltage from cranking but no ref pulses.

Code 19 leave for now but it gets set if the TPS has not varied by more than "Malf 19 - Min Delta TPS Between Loops", the calculated TPS (Malf 19 - Expected TPS vs RPM) is < than actual TPS and MAP < "Malf 19 - Max MAP for error condition". Clear the fault codes and it will clear anything that has been learned. Hopefully in a log you will see when the code gets set and can then fix it.

[vp304]

thanks heaps for the info vl400.

Disconnected the battery while i was doing the wiring work so it shoulda reset the codes

Il get a copy of my tune and upload it soon for you gurus

Code 46 could that be that when cold sometimes it takes me 10 sec or so to kick the car over due to straight gas causing it hard to start?

Car is a auto converted to manual if that makes any diffrence

[vp304]

see attachment

if it makes any diffrence xdf used is
OSE_12PV110-fixed_datatypes_for_tracing_1&2bar

[Holden202T]

i think what VL400 is refering to is to clear all the codes by removing the battery, then start the car and log straight away so then you can find the point in the log where the error codes are being set, then you can see what the iac and tps and such are at the time

[vp304]

ok heres the log. Started the car cold, battery had been disconnected. No faults besides that knock sensor.
Iac come on after a short while then about 4 mins later of driving the tps fault come up ???

[Holden202T]

it looks like from the logs that the IAC is fully opened to get the idle higher, as the engine warms up and the idle increases the IAC is closing slowly ... i would try screwing the butterfly stop in to open the butterfly more and see if the IAC decreases .... most of the time as the engine was warming up the desired idle was like 780rpm and the engine was idling approx 650rpm ..... in that case its going to continually want to add iac steps to get the idle up.

another thing you can do to test the IAC is remove it from the throttle body and connect the wire to it, then turn the ignition on and off and see if it changes position.

also remove the air pipe so you can stick your hand in the throttle body and cover the IAC port with your finger, see if it changes the engine rpm or stalls the motor....

[vp304]

Once it warms up it settles to the stock 750rpm. I tried the other day to knock the idle up by the idle screw to about 1100rpm turned the car of on rev it over 2000rpm no matter what the iac wouldnt close more than about 100 steps and the idle stayed about 1100rpm.

Here is a pic of the iac block i have been using for about 4 years. Its the way they set up all gas research setups like mine. The little feed line going to the top is jetted and comes of the low pressure side of the gas converter.

[Jayme]

take a look at the tps voltage in th emonitor screen, somehting very wrong there, it goes up and down too closely to the map voltage. id like to see a log of the engine not running and you just pressing foot on and off the throttle. i looks to me like the tps line is hooked up to a map sensor output or somehting