i recently did a N/A to TII engine swap. I replaced the engine the harness the ECU ext. It will turn over but not start. I traced the problem to the injectors that weren't putting out fuel for the engine. I tested the main relay and it's fine the wires that go from the injectors to the ecu are fine as well. So in order to test the ECU i grounded the test connector and looked to see if the check engine light would come on at all. It didn't and no i notice when i go to turn over the engine that light doesn't come on then ether so does that mean my ecu is bad? what other test can i do to narrow this down and find my problem?

Any help is appriciated. thanks

 

chech ur fuel pump connector,... pull that shield up, the connector that hooks up to the fuelpump has 4 prongs , 2 with no power 1 with a pulsing power , the other was a constant flow of power. if theirs no power , then u have a problem. if u have power change the fuelpump.

 

ok, i was having the same problem, its the fact that you probably don't have the resistor pack that allows for the high-impedance injectors to run (or something like that). there should be a yellow plug (its got 5 prongs: 1 that's always on- the other 4 go to the injectors) that's attached to the wire harness underneith the stock air filter box.

if you jumper it or actually go out and buy the resistor pack (its 6 ohms to each injector. do the math) it should start. i did this and it did start, but i had bigger problems that prevented my car from actually running and idling. good luck.

oh, and if you need more answers PM HAILERS, he's the guy that helped me out when i was having my problem.

 

the fuel pump is fine i tested that as well. I also forgot to mention mine is an S5 so i don't think i have the resistor pack your talking about.

 

i found my problem my ecu is bad

 

Where dd you get the harness?? JDM????

The ECU does not supply the voltage to the injectors. The ECU supplies a pulsed ground to the injectorrs.

I would have looked at the ECU plug, with it off the ECU and seen if there was 12vdc coming FROM the injectors TO the plug.

 

ya there is voltage going to the injectors it was the ecu that wasn't grounding it.