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Definitely need to figure out if it's lean or rich. At what engine temp does it become drive-able?

Was it fine on a cold start before the LS TB?

It may pay to put the original TB on and take a cold start log and then repeat with the LS TB and see what changes.

immortality wrote:Definitely need to figure out if it's lean or rich. At what engine temp does it become drive-able?

Was it fine on a cold start before the LS TB?

It may pay to put the original TB on and take a cold start log and then repeat with the LS TB and see what changes.

The wideband reads lean, but that could be due to the fact that it's misfiring when this occurs. The car was fine before the ls throttle body. Would be drivable within 20 seconds of starting. It has me thinking though, there might be a slight chance that there is a vacuum leak between the Ubend and the throttle body adaptor. Putting on thr stock Tb should eliminate this I think

It sounds lean to me, possibly partly each for all of the reasons mentioned above - Fuel atomisation properties at cold temp, enrichment not enough for the larger TB including the param immortality mentioned, possible air leak letting in unmetered air.

have you also considered that it suddenly got cold just recently in vic? like the temps have dropped more than 10-15ºc in the last 2 weeks alone. It was -ve at my place this morning and everything had ice on it. 2-3 weeks prior it was like early December weather.

So perhaps you might of had problems that never actually showed up until ambient temps dropped enough to surface them.

Yeah. To be honest it has been happening for a while now. 3 months+. But never really bothered me until I started driving it to work. I'll do some digging with the tb setup and find out. The parameters I've changed had no effect on this issue. The only thing which has worked well is the crank fuel vs cts.

I haven't ruled out an air leak yet.

Put on the stock throttle body. Made no difference. Looks like I need to start looking elsewhere.

bypass valve stuck?

vlad01 wrote:bypass valve stuck?

Bypass actuator works properly and the bypass solenoid has been deleted.

https://youtu.be/gkEOP_PsKZI

Here's a quick video of what it does when I touch the throttle only when cold. When it's warm, it applies my commanded afr in that region. I do have closed loop disabled. All running open loop.

Looks like going lean as fuck when you give it some throttle. Add in a whole lot of AE in the cold part of the table.

edit: hang on, your on e85 and that WB is showing petrol style AFR's. It probably is lean just idling and giving it some throttle is just killing it. You probably need to enrichen the whole cold start area.