Is there a definitive way to tell if the Fuel Injection Computer is shot. I have downloaded the usual technical stuff and can't seem to make any sense of it yet! Anybody that can give me a play by play instructions for checking it? I have narrowed my problems down to relays and / or bad computer and / or bad wiring. Fuel pump seems to be OK. Any advise guys, whats the next step?

Thanks,

Todd

1960 MGA
1973 914 1.7L

We thought my car (74 2.0 at the time) had a bad computer, just swap it out is the easiest way.

First to go are the relays, then the wiring, last of all is the ECU. Always check the relays first.

What are the problems you are having?

Geoff

Thanks All for replys. Here it is in a nut-shell. No power to the fuel pump wiring. When I jump a hot wire to the Fuel pump it works so must either relay or wiring. Tried swapping another relay off the board (not the main power one) into the fuel relay socket, Nothing. Ok so I tried giving the fuel pump power via jumper with the relays attached figuring I would see if I could just get it cough or something, Nothing! Engine does run if I squirt some gas directly into the throttle body so that is not a problem. I guess I'm at a loss and hate to just keep trying stupid things. I did order a new relay should be here in next few days. What else should I be checking in the mean time? This FI is all greek to me I'd rather sync my MG's carbs 20 times than troubleshoot this

Thanks Guys,

Todd

You can rent a fuel injection tester from Pelican http://www.pelicanparts.com/support/ecu_testers.htm .

Alfred

Look at the relay board for problems. Take it out and flip it over and look at the circuits. Since the heater booster fan and the fuel pump are on the same circuit you can burn out that circuit line with a bad fan.

Try the jumper between the fuel pump pins (refer to the PelicanPart article) and if that doesnt to the fuel pump on, take the relay board out.

Geoff

don't forget to check the fuse on the relay board.

Unplug the four-pin connector on the relay board. With the key on, check for power at the right-front pin of that connector. Hook a ground wire up to the left-front pin, and listen for the fuel pump. The ECU runs the pump by grounding the wire that goes to that pin.

You can also plug the four-pin connector back in, and poke the probe of your multimeter in the back of the connector where the left-front pin is. Check that for continuity to ground when the starter is being cranked.

--DD

Smells like the relay board to me, or a loose connection somewhere.

Patience Grasshoppa...the FI system is not that hard if you are methodical, as you already have shown us...