Might as well confirm battery voltage at the ECU connector, it should be two R/W wires, right across from each other.
When you are probing the grounding blocks, make sure you check each wire individually. The corrosion gets between the individual wires and the grounding block.
74Nitro
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I would take a closer look at the starter relay plug. The fuse on the starter relay is the fuse for the fuel injection. Inspect the Reg/Green female spade inside that plug. That is the wire that provides power for the fuel injection system.
Another test you can do is read voltage at the fuel injection relay on the R/G wire WHILE you turn the ignition on as then you will be doing a load voltage test.
I'm doubtful you have a ground problem as your code says otherwise.
Another test you can do is read voltage at the fuel injection relay on the R/G wire WHILE you turn the ignition on as then you will be doing a load voltage test.
I'm doubtful you have a ground problem as your code says otherwise.
He Jumps the injector relay and it starts and runs fine. To me this says that the R/G is fine, its enough to power the injectors and fuel pump. The problem is no ground on the coil side of the relay (Y/R or Blue/Red from ECU) at least from the description. And the persistent code is 43, no reference voltage from ECU. (open circuit). The only way that circuit is open is either because it is, or because the ground reference is gone and it just cannot get a reading (nothing to reference against). Tough to diagnose from a keyboard 
74Nitro
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Depends how he jumped it. If he used power from the Red/White that is also live there then it still could be the Red/Green issue I mentioned. Code 43 won't recognize a bad ground to my knowledgeHe Jumps the injector relay and it starts and runs fine. To me this says that the R/G is fine, its enough to power the injectors and fuel pump. The problem is no ground on the coil side of the relay (Y/R or Blue/Red from ECU) at least from the description. And the persistent code is 43, no reference voltage from ECU. (open circuit). The only way that circuit is open is either because it is, or because the ground reference is gone and it just cannot get a reading (nothing to reference against). Tough to diagnose from a keyboard
True, I assumed he meant jumping one side of the relay R/G to the other to provide the closed circuit to feed the pump/injectors.
Its a bit of a reach on my part. If the ECU has no ground reference, it also has no way to reference voltage, essentially everything is floating. Voltage is always relative to something else, typically ground. Could be floating high, low, or in between. Caveat that I think if there was no voltage at the ECU there would be some more obvious feedback. Not having a good ground or no ground at all sets up everything for not having a good way to measure voltage or even know what 'low' means. Lets say that internally the voltage is floating, what does it mean to pull a circuit low (activate an external relay). Like I said, its a reach because I have no idea what is being seen on the fuel injector relay. Also, trying to throw out alternatives in case all of the normal troubleshooting has been done.
74Nitro
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I get what you are saying, but if there isn't a ground reference then how would the ECU know voltage isn't what it's supposed to be? If the ECU is otherwise functioning(which it seems to be), it's probably got a ground source. I'd still lean towards the Red/Green not delivering a good 12V power source. According to my wiring diagram, there is more than one ground supply to the ECU.
If the ECU wasn't receiving a ground, maybe the error code is one of those "ER"-1, 2, 3 or 4 codes?
Could be... there will be a separation between pure logic circuits that can work from their own floating ground reference and controls for external circuits for which those external circuits rely on a reference to the chassis ground. I am going with.. Its an apex, if its not the pickup/stator, its a bad ground
pdiddy
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Yep - look for green gunk in the connectors.
madhatter275
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Well I want to give a follow up bc it matters to some people with the same problem.
I checked everything and it always came back to me thinking it was a bad ecu so I finally shook the dice and stole one from my buddy’s and it fired right up.
I checked the starter relay and every ground block. Had the main harness all apart, sled in pieces, but at least I got to hear that sweet sound of the fuel pump.
I checked everything and it always came back to me thinking it was a bad ecu so I finally shook the dice and stole one from my buddy’s and it fired right up.
I checked the starter relay and every ground block. Had the main harness all apart, sled in pieces, but at least I got to hear that sweet sound of the fuel pump.
blown apex
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i had one do this it was the shunt connectors seems to be several that are hidden
some are grounds and some are power
do a search seems someone had pics
i cut them all out stripped the wires soldered together then used glue heat shrink
you can wire nut 1st till you find it then solder
mine was intermitant fuel pump
some are grounds and some are power
do a search seems someone had pics
i cut them all out stripped the wires soldered together then used glue heat shrink
you can wire nut 1st till you find it then solder
mine was intermitant fuel pump
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