Ok so he's the deal, we pulled the engine to replace the clutch and clean it and the engine bay put it back in and it wont start. We check to see if it's getting fuel and it is check to see if its getting spark it is. It will turn over then back fire so we figured timing and checked it, its 180 off so we fix that and crank it again and it turns over for awhile and backfires we check it its 180 off again? so we repeated that a few times and it kept ending up 180 off. yes we making sure its at tdc. it started to rain so we called it quits, today i got back on it, made sure it was in time and cranked it a few times nothing and the bat started to die, so i check timing and its good went and got the charger and remembered i forgot to turn on the fuel pump(its on a switch) so i hook up the starter and turn the pump on and it back fires i check the timing and its 180 out again?

Im pretty lost at this point. its also throwing code 11 crank angle sensor and code 21 ignition signal circuit.

 

Engines don't just randomly stop working.
Timing doesn't randomly jump either.
If it was running as it should have been before you pulled the engine, then something either wasn't installed correctly, or was broken in the process.


How are you figuring that it is 180 degrees off?
Are you saying the cams are 180 off? Or the dizzy is 180 off?
Are you checking it at TDC on the compression stroke?

Did you remember to plug in the distributor? The plug on the side of it?
Given the symptoms and the codes, it sounds like the CAS in the dizzy is the problem. Either the plug itself is bad, which happens rather often, especially with unplugging and plugging it in a few times. Or the sensor has gone bad. Which it isn't as common, but it does happen.

diagnostic procedure for code 11 starts on page 93 start with, and solve this first as the solution could solve both issues.
http://www.nicoclub.com/FSM/240sx/91-94/EC.pdf
code 21 starts on page 104.

 

when i put it at tdc on the compression stroke at the dizzy i have it timed at and its pointing towards the front of the engine at 1 then crank it and put it back to tdc itll be pointing at 3 towards the firewall. If you take it out and spin it by hand all the injectors click and every plug sparks

 

#1 is at the top left, if looking at it from the driver's side.
#3 is the bottom left...
so if it is pointed more towards the firewall, then it is most likely pointed at #4, in which case, you need to turn the engine 360 degrees as you are not on the compression stroke of #1.

that might be part of your problem.

also, check here - Garage411: Nissan 240sx S13 Engine Performance Basic Diagnostic Procedures
just over half way down the page, it gives some simple instructions for testing the CAS

 

Here's what i do every time i have to retime an s13:
Start by pulling the number one plug and wire. Stick your #1 plug boot back in the hole and make sure it's somewhat sealed.

Crank the car until it pops out of the hole.

Set it at the tdc mark on the crank pulley.

When inserting the distributer, hold the rotor at approximately the number three spot on the dizzy (will turn to the number one spot when you slide the dizzy in.) Might take a couple tries to get it on the right tooth but just mess with it and see where you get.

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