Sever timing retard/Misfire

[m_0ney_pit]

What are possible reasons that the 2g turbo ecu would retard timing (0 degrees) around 2-3 rpm and give a cylinder # 3 misfire code?

The timing being pulled is alot...I've seen 0 degrees on my logger under the worst cases. When this happens the misfire is very bad and the tone of the exhaust gets very deep. Anywhere over 3k-6rpm rpm I see a nice 15-17 degrees of timing at 9.5 psi and the car runs great.

The car also takes alot of cranking to turn over on warm starts, cold starts the motor fires right up and idles at 1500rpm until it warms up. On warms starts however, it takes at least 5 seconds of cranking for it to turn over and when it does start to fire the motor stumbles and misfires for 1-2 seconds and then evens out to a nice smooth steady idle.

Any suggestions on where to start?

 

[ktmrider]

Any knock being detected? Also what kind of FPR are you running?
I had a similar issue when the vacuum line to my stock FPR came off ( those lM lines don't like boost without a clamp of some sort ).
Log the O2 readings, they might show a lean/rich condition at those RPM's.

 

[m_0ney_pit]

at 2-3 k rpm when the anomaly happens...the trims go waaaaay rich. Heres the clincher...found out today that when I clear my ecu code for the 2nd o2 sensor not being there...the hard starting condition goes away and it fires right up on the first crank. The 2-3k rpm timing retard condition also disappears for a pull or two...then like magic once the sever timing retard happens and misfire under boost the ecu shuts down the connection to the logger and I can't view anymore until I turn off the ecu and turn it back on! I am using a supposedly 1998 gst ecu but I think its actually a 1995-1997 non-eeprom because I'm only getting 11 sample/second on the logger where if it was a 1998 or 1999 I would be getting close to 20 sample/second.

I have the stock 4g64 FPR because no one makes an aftermarket adjustable one for the 4g64 fuel rail. I do have the fuel pressure solenoid wired in however and connected to vacuum in the engine bay. I have some light boost leaks at my 1g BOV and my couplers but the charged system holds pressure for about 20 seconds at 10 psi.

 

[ktmrider]

Ok, is the 2-3k range where you transition into boost? I had a non turbo conversion a few years back that had similar performance problems.
The vehicle was speed density and the MAP was unable to process a positive boost signal. We used a voltage clamp to limit the output signal else we got fuel and timing pulled. The ultimate fix was installing a 2 bar MAP and scaling the MAP signal accordingly to keep the ECU happy.
I'm not sure what type of tuning solution is used on the 2g turbo kit but re-scaling the MAP voltages could resolve the problem.

 

[m_0ney_pit]

Ok well I measured my coilpack resistance and my primary is at .925 ohm and secondary for
cylinders 2-3 is 23 k ohm and cylinders 1-4 are 24 k ohm. Secondary was
measured with triangular connector on top disconnected. SO this kind of makes sense...there can't be any timing if the the coilpack isn't generating any spark right?

Now I have the 4g64 nt coilpack which I believe is the same as the JDM GVR4 I know the spec for the 4g63t coil pack is 10-13 k ohm on the secondary...does anyone know what spec is for the 4g64 nt pack?