cold acceleration amount

[AVP]

How much do you find you need to use?

now that it is getting colder, it seems from various logs that my car even when the accel enrichment is adding up to 1.2 to 1.5ms of fuel, lamda does not either get low enough to not cause problems, or at least its not something i see on the log doing fast enough.

So what i get is a sense of fuel cut which slowly dissappears as the engine's temp and fluids come up.

I do have EGO on from 28C of CLT, and around the 1000-1500rpm area lamda target of 1.02.

I have : cold accel % added 120 and added ms of 2.0 (equivalent to 67% on vemstune)

my softes accel enrichment pedal press is set to 1. next step is 20.

Possible solutions:

1)Keep increasing the accel added amound %? (going to try 125)
2) get ego to start working on higher temp so that to keep the engine richer a bit longer and allow to cover for the fuel film phenomenon?

on vemstune i suppose i could manipulate the MAT vs TPS table on 0-5tps to be a bit richer on cold temps, but that could also affect cruising on cold days as well, making the consuption suffer.

any suggestions?

What is everyone else doing on cold engines?

[gunni]

Don´t mess with tables that are ready.

as they will then be off when the engine is warmed up.

add more to the cold accel enrichment in steps and see how that goes

[mattias]

I find that enabling EGO at 40 C is the lowest temperature that gives acceptable behaviour, it only takes  a couple of minute to reach that temperature from a cold engine if you drive away very soon after starting.

I haven't given it much time, but my old BMW M20 engine was totally unresponsive until I used about 300% for the "acc cold multiplication factor" and 100% "added at -40C".
These two values can be entered differently, and result in the same outcome at certain temperatures, it would be nice with a graph..

[AVP]

ah thanks for that guys. ill try that. It hasnt been that cold here yet and up till recently i thought i had it nailed. So i will do that with the accel added amount.

cheers

[AVP]

i think i have found my problem. In my search to make the car run economically, i have been using EGO correction from 28C CLT. Today, i used the same settings with ego OFF and the car went fine, drove around a little bit and as soon as i put the EGO on, it happened again. CLT was about 40C at the time. So i put now EGO starting from 45C, and i reduced the cold added amount to 118 from 125 which i had upped a bit without any improvement.

when i think about it, the fuel cut like reaction was coming more slightly after i had pressed the accel pedal and the enrichment was finished 0.5sec after. SO hopefully this should work now. ON EGO OFF till 45C i was noticing that with the accel enrichment being that high, lamda is reacing 0.7x ish and idle is around 0.94. so it should be ok for cold status now. But i reduced the enrichment values so that it doesnt become overly rich when EGO is off.