my ride vt ecotec

[immortality]

the idle stability is the issue it just wants to stall from time to time coming down of rpm or of a first start but after you hold the throttle open for a bit and allow it to slowly return to an idle its mostly fine you sort of have to drive it like a carby car its a bit of a pain specially if theres traffic

Kinda sounds like my missus car. Engine stalls on a cold start but it fine once it's warm.

Our problem occurred with I fitted a 69mm TB that was for a VS onto our VX which has a slightly different IAC (bigger passages and stepper motor pintle).

Check the IAC steps when the engine is up to operating temp, should be roughly 30-40 steps I believe with no extra load on the engine.

What I did to reduce the issue was copy some of the VS cold start, open loop and IAC tables into the VX tune, this reduced the problem but didn't completely fix it. ATM I'm experimenting with some other tables.

Edit, Yours been cammed you probably want to increase the idle rpm as well as the cold start target rpm until it warms up and settles a bit. IF I remember correctly you've got a decent size cam which is going to have a moderately choppy idle anyway and probably won't be happy at the OEM idle rpm targets.

[Holden202T]

atre you anble to post a log of starting it stone cold ? and also your calibration ?

i have had a bit of a play with iac settings and stall saver to work better with my new cam ..... i didn't have the same issues with other cams but they were never as big as this one

the other thing to take notice of, when it first starts if you use the throttle to get it going, does it sound at all like its flooded ?

[vt3.8lt]

Im not sure if i have a log of it cold starting but im sure i can get one as soon as i have a chance and i can pull a cal from the nvram at the same time

It did seem to be flodding at cold start had a play with the inj puse width vs coolant temp on cranking maps and it seems to have sorted but for some reason it keeps changing one of the hotter temp numbers to like 128 and it just dloods once it gets hot might have a log of it doing that but my wideband isnt working on logging so i need to look into y that is

That iac settings and stall saver stuff is a bit byond my knoledge yet i tried to have a play with it and didnt seem to help much so i thought it may have just been the cam so made a iac delete and just set idle with the butterlfy and tune but im going to put it back in place and see if i can get it to work found that my lower intake gaskets werent toatally sealled so i think that may have been contributing to it being a pain

[Holden202T]

well if you can get the website working in the logs and a cold start log with IAC working I can probably help with it

[vt3.8lt]

sounds like a plan i appreciate the help ill look into getting those for you soon as i have a chance if i can find y the wideband isnt logging

its a shame clutches are so expensive for this thing considering for one the same for a silvia its like half price thats supply and demand for you though

ivr got the desired idle slightly higher than normal 900-1000 rpm im not sure where to find that cold start target rpm if it is even in the 11p the choppy idle doesnt bother me its when it stalls and you have to keep it running is a pain in the but specially at the track it looks a bit sloppy

[Holden202T]

yeah you might find the desired idle needs to be higher, will just be a matter of trial and error, and theres stall saver rpm settings too, you want to increase them to about 200rpm below desired idle.

also make sure the iac steps at warm idle is 10-20 will make it happier than a higher number

[vt3.8lt]

Hey guys i spent a bit of time on the commy this morning i didnt get any logs as i said i would the wideband doesnt want to log for some reason im srill trouble shooting it but i removed the iac block off and re installed the iac motor and it idkes a heap nicer than before doesnt really stall anymore ecept fot the od occasion i found and changed the iac stall saver to a couple hundred below the desired idle not i just gotta get a clutch into this thing aswell as a diff then its off to they dyno or back to the track

[Dylan]

Have you removed the pull up resistor on the ecu for the wideband input? That caught me out.
The 808 works fine with that still on the th e 424 doesn't.

[vt3.8lt]

Yeah dud that ages ago it would still work but if it was in place it would just read wrong

Also im hearing a clack from down in the valley i think it may be the anti pump lifters but im not 100 percent sure andone else run them and had them clack away?

[Dylan]

What do you mean read wrong? Where is it fitted? Have you seen the 0 and 5 volt scalars to adjust the readings? Does your controller have a calibration feature?