Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum - View Single Post - SR20DET . ECU dropping timing to zero on throttle.. MIND BLOWN any ideas?

GhostlyCoupe · 03-18-2012, 04:51 PM

The car:
PLMS daughtercard
Freshly rebuilt SR20DET
100% stock including SMIC

Symptoms:
Lack of power
Backfiring under boost
Bogging when applying throttle
Code 55 (no codes, knock sensor bypassed with 1m Ohm resistor)

Diagnosis:
Using NDS I was able to log what the car is doing. When throttle position is greater than about 1/4 ( >1.0v ) the ECU is retarding timing to 0 and upping injector duty to almost 40%.

I used the map trace and it's going into the +20-30 timing range on the map but for some reason the ECU is just dropping the timing to 0.

I'm kind of stumped on why the ECU is retarding timing and upping injector cycle so bad. Any ideas?

03-18-2012, 04:51 PM	#1
GhostlyCoupe Zilvia Member Join Date: Dec 2011 Location: Phoenix, AZ Age: 42 Posts: 221 Trader Rating: (1)	SR20DET . ECU dropping timing to zero on throttle.. MIND BLOWN any ideas? The car: PLMS daughtercard Freshly rebuilt SR20DET 100% stock including SMIC Symptoms: Lack of power Backfiring under boost Bogging when applying throttle Code 55 (no codes, knock sensor bypassed with 1m Ohm resistor) Diagnosis: Using NDS I was able to log what the car is doing. When throttle position is greater than about 1/4 ( >1.0v ) the ECU is retarding timing to 0 and upping injector duty to almost 40%. I used the map trace and it's going into the +20-30 timing range on the map but for some reason the ECU is just dropping the timing to 0. I'm kind of stumped on why the ECU is retarding timing and upping injector cycle so bad. Any ideas?