Greasy Paws

New guy here to the Nissan world. I am a mechanic with 26 years experience and finally got under the hood of a 3rd gen 1991 Nissan Maxima VG30 auto trans. Customer car. Drove into the shop for engine replacement. Replaced engine with used low miler. Swapped over all parts and sensors from running engine. Cranks over sputters a bit but will not start. Code 21 from the ECM. my manual ( Haynes) says take to dealer for repair of code 21.. I am getting consistant spark. Fuel pump works. Timing is spot on. Tested and retested about everything I can find. I reswapped all coolant sensor, throttle position sensor,new coil, new cap and rotor, 2 distributors,cleaned plugs. swapped power transistor thingy.At a loss here guys. I searched thru the threads here but didnt find any info. I work on anything and everything. I am doing videos of this Maxipad for my youtube channel but am stuck with a non running car.Any ideas?

thanks guys
Greasy Paws
My Youtube channel: Greasy Paws Garage
I will give a shout out on my channel about this site

The Wizard

iTrader: (43)

Perhaps these threads will help you, if you haven't seen them already.

https://maxima.org/forums/1st-2nd-ge...lfunction.html
https://maxima.org/forums/1st-2nd-ge...code-21-a.html

Greasy Paws

well so far you have steered me in the right direction. i now have full consistant spark. power transistor was bad. now 2 more questions: what should fuel pressure be? and the hose from fuel filter goes to the regulator side of the fuel rail correct? not the other way?

Thanks for the assistance
Greasy Paws Garage