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Nikzilla · 02-13-2014, 09:24 PM

BIG UPDATE:

So I swapped the plugs (they were gapped to ~.37), started the car, put the ECU into base idle adjustment mode (locks timing to 15) and put a timing light to it.

It read -30. Fuck. CAS must have slipped. I set it to 15 and re-torqued it, bumped up the IACV to match as well.

It's almost undrivable.

Here is what happens.

Low RPM, low throttle, it drives fine. As soon as I let ANY boost build, the timing gets pulled back to 0, my fuel pressure spikes to 60psi, wideband dives down to 12, and the car makes no power. It's slower under boost than without boost.

As far as I can tell, the previous issue is still there, but it's really sorta hard to tell because of how fucked everything is right now. If I just try to hold it at 2500 RPM, the narrowband spikes rich and wideband spikes lean. The shit part is, I can't correct it by spiking the throttle anymore, because then it builds boost. It was impossible to get the car past 3,000 RPM.

But, GOOD NEWS! The duty cycle started behaving!

Here is the data log:

The only thing I can think of, is that the .37 plug gap is somehow reacting with the boost.

Fuel:
Walbro 255lph
Z32 filter
Stock FPR (But I have a Tomei Adjustable sitting in my garage which I haven't installed yet)

P.S. When I pulled the spark plugs, they looked dry, with a bit of powdery white on them, which is a big change from black when I was running rich a month ago.

02-13-2014, 09:24 PM	#47
Nikzilla Zilvia Member Join Date: Jun 2013 Location: Los Angeles Age: 29 Posts: 291 Trader Rating: (0)	BIG UPDATE: So I swapped the plugs (they were gapped to ~.37), started the car, put the ECU into base idle adjustment mode (locks timing to 15) and put a timing light to it. It read -30. Fuck. CAS must have slipped. I set it to 15 and re-torqued it, bumped up the IACV to match as well. It's almost undrivable. Here is what happens. Low RPM, low throttle, it drives fine. As soon as I let ANY boost build, the timing gets pulled back to 0, my fuel pressure spikes to 60psi, wideband dives down to 12, and the car makes no power. It's slower under boost than without boost. As far as I can tell, the previous issue is still there, but it's really sorta hard to tell because of how fucked everything is right now. If I just try to hold it at 2500 RPM, the narrowband spikes rich and wideband spikes lean. The shit part is, I can't correct it by spiking the throttle anymore, because then it builds boost. It was impossible to get the car past 3,000 RPM. But, GOOD NEWS! The duty cycle started behaving! Here is the data log: The only thing I can think of, is that the .37 plug gap is somehow reacting with the boost. Fuel: Walbro 255lph Z32 filter Stock FPR (But I have a Tomei Adjustable sitting in my garage which I haven't installed yet) P.S. When I pulled the spark plugs, they looked dry, with a bit of powdery white on them, which is a big change from black when I was running rich a month ago.