The code is Ignition Signal but how do I fix the problem?
My dad brought his Xterra back from a repair shop last night and this morning he drove it down the road about five miles and he said it quit like it did before. When he took it to the shop he thought it was the timing belt that snapped. So he had it replaced. He thought it was the timing belt again this morning. My dad said if the timing belt is good the distributer rotor rotates, which it does. I talked to the mechanic at the shop and told him the problem. He said to check if there is spark.
I read a thread about a bad distributer and it needing to be replaced because it controls three things. would this be the problem?

According to this:

http://www.nissanhelp.com/diy/obd_codes/p1320.htm

It could be a harness, ignition coils...

The fact that it starts and runs then later dies I would have the crankshaft position sensor checked as that is on the list also and could cause it to die if that sensor isn't working.

I'm not sure and not a mechanic and I'm sure others will have some ideas.

But I don't think it's to do with the timing belt.

Is there another code that comes up as well like a P0301,302,303,304,305,306? If so then there is a misfire detected in that cylinder and it's probably a bad ignition coil.

Are there any warning signs before it dies? Like sputtering out, etc.?

The other codes that showed up are PO325 and PO335. Knock Sensor Left bank and Crank Shaft Position Sensor. Would these cause the car not to fire up? The engine turns over but doesn't fire up, no spark.

One of my dads friends from England noticed there was a loose wire connection to the distributer. That caused it to have no spark. Thanks for the info. I'm sure the knock sensor and crank sensor will have to be replaced.

The CPS will probably need to. It's probably what's causing it to die.

The knock sensor code will always be there and is expensive to fix. Not really necessary to replace as that code won't actually trip the CEL to come on. Won't hurt anything.