Dyl510
10-03-2010, 03:18 PM
Engine starts/runs fine, but once at operating temperature when I put it in neutral (when coming up to a red light) the RPMS drop really low and it often stalls out completely.
I've been messing around with this issue for the last few weeks, and I'm about 99.9% sure that the AAC valve isn't operating properly. The entire AAC/aux air valve assembly is brand new and clean. When the engine is idling at operating temperature and I unplug the AAC harness... nothing happens.
Looking at the AAC harness, 2 out of the 4 wires run to the AAC (black/yellow and light blue), the other 2 darker blue wires run to the aux air valve (which apparently only feeds more air during cold operation... and I have no issues while the engine is cold).
With the key/ECU on, the black/yellow wire shows 12v, and the light blue wire shows almost no voltage (around 0.30v). Resistance between the two AAC terminals is 7.7 ohms... FSM says it should be 10 ohms.
I'm suspecting an error in the wiring somewhere, but I don't really know where to begin!
I read somewhere that the power supply for the aux air valve runs off of the fuel pump relay. This engine is in a non-Nissan hot rod project, so my fuel pump relay is wired off of an toggle switch and the aux air valve is not connected to it. However, as I said before, the aux air valve affects cold operation and does not seem to be giving me an issue.
Does this sound familliar to anyone?
I've been messing around with this issue for the last few weeks, and I'm about 99.9% sure that the AAC valve isn't operating properly. The entire AAC/aux air valve assembly is brand new and clean. When the engine is idling at operating temperature and I unplug the AAC harness... nothing happens.
Looking at the AAC harness, 2 out of the 4 wires run to the AAC (black/yellow and light blue), the other 2 darker blue wires run to the aux air valve (which apparently only feeds more air during cold operation... and I have no issues while the engine is cold).
With the key/ECU on, the black/yellow wire shows 12v, and the light blue wire shows almost no voltage (around 0.30v). Resistance between the two AAC terminals is 7.7 ohms... FSM says it should be 10 ohms.
I'm suspecting an error in the wiring somewhere, but I don't really know where to begin!
I read somewhere that the power supply for the aux air valve runs off of the fuel pump relay. This engine is in a non-Nissan hot rod project, so my fuel pump relay is wired off of an toggle switch and the aux air valve is not connected to it. However, as I said before, the aux air valve affects cold operation and does not seem to be giving me an issue.
Does this sound familliar to anyone?