240: injector issues

[Bloody244]

after my old head blew apart i installed a new one. now it wont start i got spark, fuel pumps works and the injectors get 12v when cranking and 0v with ignition on, on both wires. i have no clue why or how it happend the only thing i did was put on a new head. lh2.2 with orange tops
ezk117 swap

[TestPoint]

Injectors operate on ground from ECM.

You should see the 12v on both sides of the injector connector without the grounds. It is just the supply voltage through the injector coil.

You are missing the ground pulses. Start at the CPS and connections to the ECM. Messing with the head is close enough to have disturbed it.

[Janspeed]

Originally Posted by Bloody244

i have no clue why or how it happend the only thing i did was put on a new head.

Are you 100% sure you got the cam timing right when you installed the new head? 180 degrees out is a likely error.
the camshaft (and auxiliary shaft that drives the dizzy) turn at half the speed of the crankshaft. You could have lined up the cam belt perfectly fine but still be 180 degrees off. There will be no mechanical consequences.
It happens to many mechanics at least once in their wrenching career.

On a 240 you have to consider the auxiliary shaft as well because the distributor is driven from that shaft.
Put the cyl#1 on TDC (check the mark on the crank pulley), both cam lobes of cyl #1 should be pointing up (= no valves open)
Take the dizzy cap off and check at which cylinder wire the rotor is pointing. It should point to the wire that is connected to #1 cyl. (firing order: 1-3-4-2, cyl1 is closest to the cambelt side of the engine)

If it is all the way it should be the engine should start.

[Bloody244]

thanks for the responses i will check tomorrow and see if i got the cam timing wrong