Car won't Start! Just finished rebuild.

[shEck3lls0]

Well. I have everything back together. I just did a full rebuild of my engine. I have it all back in the car and its not wanting to start for me. All I am getting is a backfire every 10 cranks or so. I am not sure what the culprit is. I have been told to check the MAS. What could the issue be? I have checked timing twice and its good. Any help out there? It is greatly appreciated.

[bmwm42]

try the crank wheel make sure you dont have it 180 out

[shEck3lls0]

Bump. Except now it kinda stumbles to start, but it doesnt. Need help on either timing or diagnosing.

[AndrewBird]

Check if you have fuel. Check if you have spark. If you have both of those, then your timing is off.

[318iBrilliantRot]

try the crank sensor

[carbeater]

what did you do to fix, im having same issue, it sucks, HELP!!!

[shEck3lls0]

Here is what I did.

First thing, how long did your car sit? Gas might be bad or have moisture, etc in it. Same with your gas lines. I would of stabalized it at least. If not, they have additives to absorb the moisture. also, make sure you change your fuel filter if it sat as well.

I replaced the crank sensor myself and got a shop to check the timing. They told me the crank and cam sensors were bad and wanted $700 to replace them. (Crazy if you tell me) The crank sensor was $90 and took maybe half an hour to put on. I didn't bother with the cam senor though cause I put mine on a friends car and it worked fine.

Before you do that however, check to make sure you have spark and the correct order on the wires. Firing order is 1342. But the numbers on the coil packs should match up with the number of the cylinders. 1-2-3-4 starting from the front of the car.

If you still are having problems, I would maybe pull the injectors and clean them if they are gunked (I can't imagine you didn't do that before putting them back in, or if you got new ones).

I will try to think of anything else that might be the problem, but check those things before you buy the new sensor.

Let me know how it goes and if you need help with anything else.

Edit: Also, make sure you did the timing chain correctly. There are a couple threads around that help with getting the timing chain right. Just search and you'll find em. You have to make sure the arrows on the cam gears are straight up(in relation to the crank) and that the arrow(located on the side of where the oil filter attaches) points to the notch on the harmonic balancer.