steve84GS TII

The actual "ground" for the injectors is inside the ECU.
The injectors are fed constant power from the main relay when the key is on.The ECU cycles the injectors on and off by momentarily connecting the injectors negative wire, to ground.Most of the engine and smog control solenoids are controlled in this fashion.The grounds throughout the main harness and near the ECU are likely to be responsible for getting all those signal from the solenoids and ECU,to the chassis ground,but there may not be an actual "injector specific" ground wire.

Make sure the trailing coil and trailing ignition system is hooked up and working right.The ECU needs to see that signal for the injectors to work.......

RXnos1200

iTrader: (24)

Fuel injectors work by applying a constant 12v to one connection and the other side goes to the ECU. This is should also be 12v when the car is not running. The ECU fires the injectors by pulling its side from 12v to ground. This put 12v across the injector causing it to open. Fuel injectors are essentially solenoid that switch the fuel either on or off. The amount of fuel injected per squirt is controlled by how long the injector is held open, not by opening the injector partially (like a valve). Injectors are either on or off type devices. Because the person had 7v when the car was not running, the injector was partially opening with the 5v or so differential across the injector, so it was injecting some fuel during times that it shouldn't.

By testing the ECU, you can at least eliminate it as a problem. If it checks out, I think that I would check the AFM next. It is also a pretty simply proceedure (testing resistance across various pin with the door open or shut). Is your AFM flapper closing correctly? If it is sticking, you will get a rich mixture at low throttle/ idle. got this from Kent ( gsl-se addict ) an earlier post.

May want to see if your getting any power to the injectors.

bugman1973

where is the main relay every one talks about them but i cant find them where are they located what do they look like and does any one have pics

bugman1973

We also are having a problem findind the main relay if the ground are hooked up which and looks ok still no pulse to the injectors. we also have to find the main relay for the injectors we did this swap on the fly and it is killing us the plugs are dry so no fuel the rail has fuel power looks good. we have 12v to the ecu in and out we have tried all that you all have given to us . thanks wil keep trying pics helh us a lot.

bugman1973

I have a few more questions for you all. Next to the ecu is a small black box that at this time is not hooked up we need to know what that is for ? and is there a main fuel relay for the 13b we see it on the diagram but not n the car? do we need this fuel relay the diagram shows 2of them on the frivers side

Manntis

something occurred to me last night; if you floor the throttle on startup and hold it, you can 'cancel' the injectors. This helps alleviate flooding problems by cutting the fuel as you crank, allowing the chambers to clear themselves. Perhaps your throttle switch is stuck in this mode?

bugman1973

Thanks we will try it and see

RXnos1200

iTrader: (24)

Have you checked to see if the injector wires have any volts to them. Seems like they should have some voltage going to it when the ignition is on.

bugman1973

does this little black thing with the yellow connector for anything

RXnos1200

iTrader: (24)

Oh the main relays are located on the driver's side fender panel right by next to the master cylinder.

RXnos1200

iTrader: (24)

Sorry spending Father's day with my nieces so I don't have the 7 with me.

bugman1973

i dont have them i guess ill have to go find some on Monday at one of our local shops the guy is on the forums he got one of the quickest ones around hopefully ill be right up there with him soon.

bugman1973

does anyone have pics of these main relays?