VL Walkinshaw Build Electronic Issues

[Gareth]

Code 44

O2 sensor lean

[kojab]

Top of page two you show a picture of your memcal as being AMBX6968. I am not familiar with this BIn. The bin I am familiar with is AMBX7274. Could it be your AMBX6968 is running the VL code ??

Check this out: http://myobatlas-production-apac.s3-ap- ... +Codes.pdf

Code 44 - System Pass (OK) - With A/C

['quipt4it]

One thing I did think of after posting was to take a sample of a few spark plugs. See if it does tie in with the trouble code.
Try and get closer to 4.9-5.0v at WOT. I would fully close the 2ndry air valve, as a slightly open 80mm T-B will let in more air than you might think. Use the primary to control initial idle. This would mean you would have to reduce voltage even further (from the previous 1.03v). You mentioned taking a video of the car running, that is a good idea.
Looks like a nice ride

['quipt4it]

Just wondering if you may have the IAC vacuum hoses ( I am assuming there are 2), per photo, ass backwards.
Not sure if this is the exact same set-up as yours.

[Nzer]

Top of page two you show a picture of your memcal as being AMBX6968. I am not familiar with this BIn. The bin I am familiar with is AMBX7274. Could it be your AMBX6968 is running the VL code ??

Check this out: http://myobatlas-production-apac.s3-ap- ... +Codes.pdf

Code 44 - System Pass (OK) - With A/C

I do get code 12 when I reset the ecu. Could the memcal change this to 44?
https://vimeo.com/490438537

[Nzer]

One thing I did think of after posting was to take a sample of a few spark plugs. See if it does tie in with the trouble code.
Try and get closer to 4.9-5.0v at WOT. I would fully close the 2ndry air valve, as a slightly open 80mm T-B will let in more air than you might think. Use the primary to control initial idle. This would mean you would have to reduce voltage even further (from the previous 1.03v). You mentioned taking a video of the car running, that is a good idea.
Looks like a nice ride

It’s definitely not lean. Plugs are ok and it’s a little sooty out the rear.
This is a video of what the IAC is doing. You can hear it closing off and starving it of air. I was thinking the same thing with the secondary TB being slightly open.
https://vimeo.com/490338141

I will get some videos done to show what it’s doing. I’m over my Vimeo upload limit.

Thanks man. It’s been a loooooooooong build. I’ve keep some of it recorded on Instagram. Now looking at this forum I could have maybe had a build thread going on here.
https://instagram.com/twr_vl?igshid=dukl1v0yr8y0

[Nzer]

Just wondering if you may have the IAC vacuum hoses ( I am assuming there are 2), per photo, ass backwards.
Not sure if this is the exact same set-up as yours.

It just uses the one block factory. Only thing I’m not running is a PCV valve. This is blocked of at the secondary TB as I am running a catch can.

[Nzer]

From the service manual. Adjusting the primary TB and making the TPS adjustable seem like a good option.

[kojab]

I would concentrate on getting the TPS voltage down first. It's not allowing the engine to go into iidle mode. As someone else said file the TPS sensor if you can or as I said before open the secondary throttle body slightly.
You will know if the secondary throttle body is opened too much because it will be idling too high. Good to here you have code 12. This threw me way off. Its possible the code 44 maybe caused buy a faulty ECM.
Many of the Delco 808 ECM are crook. Best to get yourself a VR or VS manual ECM.

['quipt4it]

That IAC looks to be OK. Depending on the steps and the opening, the idle speed appears 'normal'.
However, when the pintle seats, the engine stalls, as there is not enough air flow around the throttle blade.
You do have the hose connected in normal running don't you
Remember the size of the orifice created by the calibrated hole in the IAC block plus the IAC pintle position will determine the amount of air 'leaking' in from atmosphere. Considering this, I thought it would be idling higher than it shows.
I was also going to suggest going in for full tuneability. It's really only worth it for the '424 delcos though, as you have much more areas to tweak.