Help me AEU86, you're my only hope

[Nakilad]

(03-26-2021 11:17 PM)jondee86 Wrote:  The OP (good Kiwi by his nick) is showing a lot of determination,

Cheers... jondee86

10/10, Give that man a cigar!

(03-26-2021 07:05 AM)jondee86 Wrote:  This thing you have been doing with the crankcase breather is interesting
too. By pinching the breather you are letting blowby pressure build up inside
the engine. Blowby contains unburned hydrocarbons amongst other things,
and when you release the pressure there will be a rush of "enriched" gas into
the intake manifold which then enters the combustion chambers. It appears
that this creates a rich mixture for a few seconds and this is seen by your
sensor.

This in turn suggests another experiment that you could try. Get 12V from
the battery positive and use it to energise the cold start injector while the
engine is idling. If that does not send your mixture rich, then nothing will

Cheers... jondee86

That was the idea. I have since tried a FWD throttle body on it (you can see a few new videos in the playlist), which has the effect of blocking the breather and that gives some interesting results as well (see below).

Once I take the fuel pressure gauge off and put the cold start fuel line back on again I can try that second idea.

So, I fitted and tested the heated NB sensor this afternoon. Seems to have raised more questions than answers, but totta was right, it clearly reads better than the unheated one, so thanks for that idea totta! Turns out that this says the car is running rich! With some caveats I will try to cover the details, but the videos I added to the playlist here should help with any questions.

First: the gauge says rich, its relatively stable at idle and does not change much when adjusting the CO2 resister up or down, untill it reaches a point where it is completely unstable and jumps around like a mad thing.

If I leave the CO2 resister roughly in the middle, and block the ventilation pipe it shows a stable rich mixture. As soon as I open the breather to atmo, the gauge jumps about again (in one of the vids).

To Note: the throttle body on the car at the moment is from a FWD, therefor attaching the breather hose to the inlet manifold has the effect of blocking it since the vent hole in the throttle body is on the other side. The car has a map sensor so there shouldn't be any un-metered air getting in, but of course the crankcase should be slowly getting pressurized.

So to summarize, adjusting the CO2 still has little to no effect on the mixture, although the change in note of the motor can be heard (rough idle at both full rich and full lean adjustment).

For tomorrow, I will put one of the two RWD throttle bodys back on (don't expect much change from this), remove the fuel pressure gauge and put the cold start injector back on (so I can test jondee86's idea). I have to get a new battery before I do much of a road trip since it seem both of the ones I have here wont hold charge anymore!