lol, Im porting a set of 350z heads right now, and installing Crower cams and springs. Remind me tuesday, Ill look them up when I go back to work if someone doesnt answer first. i dont remember those off the top of my head

 

Lentz, Codes P1383 and P1388 are both for the variable valve timing circuit being overly retarted (timing that is, not being dumb). P1383 is for bank 1 (cylinders 1,3,5) and P1388 is for bank 2 (cylinders 2,4,6). The possible causes is:
1) wiring problem between the PCM and the actuator
2) stuck actuator
3) actuator oil supply fault

Possible problems 1 and 2 would require 2 separate faults to make them occur. While possible, unlikely unless your friend has been living with one of the problems for some time. So, that leaves an actuator oil supply problem. HOw long has it been since your friend last changed his oil? If it has been a long time, I would start there and see if things improve. May want to consider running an oil detergent through the engine to help clear out some of the gunk if this is the case. Beyond that, not sure what to say. I don't know the insides of these engines well enough to go much beyond this. But, hopefully this will atleast give you a starting point.

 

yes I have this problem as well now reading on my 2002 stype 4.0L now and two other codes. Were you able to resolve this issue? Thanks

 

Stype, something you may want to try is getting a bottle of oil detergent (I use stuff called CD2). Add that about 100 miles before you next oil change and then drain out your oil like you would any time you change the oil. This bottle is simply the detergents that get added to normal oil. But, in this case, you are adding some extra and I have had motors that have responded very well to this product (only like $3). Some motors though have not been affected by the extra detergent. But, it is a cheap thing to try.

As you are adding the detergent, do a quick look at the plugs for the VVT. If you are going to have an issue with the wiring, this is the most likely place. Also, did you recently do anything to the car? Just trying to eliminate likely sources.

 

Be sure your using 0W20 or 5W20 oil - good national brand - I use Castrol - substitute 1 quart of the oil with automatic transmission fluid - If your VVT soleniods are clogged this should help clean them. I had the P1388 issue even after the re-flash and no dice. I used this method and the P1388 cleared up within 150 miles of driving. Transmission fluid is highly detergent. It's a cheap option to try - good luck!