355 5.2, no injector signals on bank 1

Fig11_1998_F355_5.2_Engine_Control_System

All 8 injectors have a common power source. There should be 12 volts on one pin of each injector if the ECU has provided a control signal to relay M in the footwell. If one bank is failing, then it must be an ECU control problem (or a faulty wiring splice 30009 or 30013). If relay M failed, you would have no injectors, no fuel pump, no... lots of things.

Here's another diagram showing the other side of plug 41090 (aka 41051)

Fig11a_1997_5.2_Injection_System_Ignitionv2

I suppose it could be a bank shutdown signal (high CAT temp, etc), false or otherwise? Or does bank shutdown only cut off ignition? I keep forgetting.

 

CAT temp shuts down injectors.

 

Interesting. Then it's a wiring problem. Have you checked the volts at the other injectors? If low also, but somehow still operating, check that pin 4 on plug 41051/41090 hasn't been pushed back. The 9 pin plug is right next to the ECU.

 

If all injectors are low, you could also try disconnecting the fuel tank vent solenoid valve and the exhaust bypass solenoid valve to see if the volts go up.

 

Doesn't make sense. There would have to be some current through a resistance to drop the voltage. If all is disconnected there would be no current draw.

 

Ah, looks I missed the "drive" in Mitchell's comment. Ignore my last messages, unless you mean "drive" = "power"

 

Ouch. Seems so. Unfortunately, we don't know where the splices are. I'm starting to regret giving my old engine harness away. If you look at photos of harnesses online, you can probably get an idea of where the harness splits into two.

 

I thought if you had a power supply problem to all injectors, these devices could have a too low resistance (partial short), dragging down the power circuit. But since the volts are ok on your other bank, these devices will be ok.

 

Sorry, deleted my last post. I misread your post again I basically said what you already said.

 

The wire gauges are shown in the diagram i.e. 0.5mm^2 (20 gauge). This is up to the splice. If you can pull back one of the injector boots and attach the additional power wire (from pin 4) to the green/black wire, you should be ok (as each injector wire is capable of taking the current of all four injectors).

 

Looking at online pics of the harness, it looks like the splice (30013) could be anywhere from the section you unravelled to the fork in the harness, so probably on top of the fuel tank.

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Splice 30009 could be close to 30013... or not. Could be a lot harder to find.

Anyway, good luck with the temporary rewiring. Might look messy, but it may allow you to drive your car.

As they say in the electrical trade, if you can't figure out where the problem is, go to the last modification which was made (on the car).

 

Is that large "P" clip attached to the top of the tank?

I see there is some insulation damage in the splice area in the photo above. I wonder what the odds are of your harness being the same.

 

For tomorrow...

Ah, you mean 30009? Or does the wiring double back from splice 30013 to the main fork? I've seen that a few times.

 

Nice trace guys