P3434 CEL code

SouthArk370Z

From what I could tell, that's not a Nissan-specific DTC. It's part of the standard set of codes. It was mentioned (but no specifics given ) on several non-Nissan sites.

IMNSHO, resetting the ECM (I'm assuming you mean pulling the battery cable) is an all-else-has-failed solution. Sometimes it's needed, but I put it fairly low on the list of things to do. I suggest using an OBD scanner to clear codes before resetting the ECM. YMMV.

You can buy an OBD scanner for well under $100 nowadays (some < $30 according to a quick web search) that will allow you to read any DTCs (modern cars can be amazingly good at diagnosing themselves) and clear them. Most of the "fancier" ones will allow you to monitor fuel trims and other parameters when troubleshooting. Well worth the money if you do any engine/drivetrain mods. I have a ScanGuageII on the dash displaying vehicle speed (so I don't have to look down at the speedometer) and engine coolant temperature (the dash gauge sucks).

Edit: I'd also recommend that you download the FSM (link in my sig). Great resource.

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