4.3L Volvo penta gxi no power to coil

bruceb58

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Eventually you want to get the wiring diagram and manual for your model. You want an OEM manual. Since you have a Gxi, you likely have multi port fuel injection right? That diagram is for TBI. It may work for now for the ignition problem but it may lead you in the wrong direction. Just my $0.02.
 

Trav2015

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The model number is 4.3 GXI-G and its production period was 2006-2007 according to the serial number
 

alldodge

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I'm a Merc guy, but there are many similarities between Merc and VP. There are two relays on the motor, one is for main power relay (MPR) and the other is fuel pump. When you turn the key to ON you hear the fuel pump turn on. If this is the case remove the two relays and swap them with each other, they are both the same. Turn the key again and see if the pump turns on.

If this checks out, check for power on Red/Purple wire coming from the MPR with key ON. If you have power (12V), turn power off and remove connectors on ECM and see if they need cleaning. Do not reinstall connectors and check for 12V on R/P wire at ECM connector when key is turn back ON. If 12V is present, turn power OFF and reinstall connectors. Check grounds from ECM and from battery. If none of this helps need to see if there are any codes showing up by using a scanner
 

Trav2015

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I have swapped the relays and they click and the fuel pump runs, what is the MPR? I will be checking and testing it this morning to letcha know what I find, thanks
 

alldodge

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I have swapped the relays and they click and the fuel pump runs, what is the MPR? I will be checking and testing it this morning to letcha know what I find, thanks

The MPR is the Main Power Relay, one of those two relays you swapped was the MPR, the other was the fuel pump relay. Both are the same type relay
 

Trav2015

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I have noticed that when I touch the white with blue tracer wire at the MPR relay with my test light it clicks
 

alldodge

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I have noticed that when I touch the white with blue tracer wire at the MPR relay with my test light it clicks

Need to do your testing with a meter, not a test light. As a non-VP expert I would say that the W/B wire which probably goes to the ECM is used to apply a ground to energize the relay. By using a test light and not a meter, the light applies enough of a ground to energize the relay.
 

bruceb58

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Don't probe anything with a test light. You will blow out the ECM if you happen to probe the wrong input or output.
 

bruceb58

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So, I am curious/confused. I thought you were debugging an ignition issue. Why are you testing the fuel pump or is that also an issue?

if I were you, remove the relays, put a jumper between pin/socket 87 and 30 of each relay(thereby bypassing both relays) and see what happens. If that works, replace the fuel pump relay and then see what happens.
 
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Trav2015

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I have now checked for 12 v at the MPR relay on the red/purple wire! It's got 12v there. I then removed the the connector off the ecm and I am receiving 12v on the red and purple wire there as well!
 

bruceb58

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That red/purple wire get's its power directly from a circuit breaker. It also feeds the relay but you need to look at the voltage after the relay with the ignition on.
 

alldodge

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That red/purple wire get's its power directly from a circuit breaker. It also feeds the relay but you need to look at the voltage after the relay with the ignition on.

Unless there is a miscommunication he does not have 12V on the purple wire in post 3

The gauges all light up, engine turns over,yes there is power at battery,key switch and the starter. Ha I gotta say it's got me kinda stumped without a schematic. I have power at the alternator as well

The gauges light up and the engine turns over there is 12V to the purple wire which is the other side of the relay of the red/purple
 

Trav2015

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Ok I'm sorry for the misunderstanding guys.... Original problem is that I have no spark! Yes my fuel pump runs while key is on! I originally replaced the coil thinking that was the problem! However I am still not getting 12v to the coil! I have swapped relays around and still makes no difference, I am using a blue point meter to test for voltage, sorry guys for the misunderstanding I am still working at it and I thank u all for being patient and helping me
 

Trav2015

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So, I am curious/confused. I thought you were debugging an ignition issue. Why are you testing the fuel pump or is that also an issue?

if I were you, remove the relays, put a jumper between pin/socket 87 and 30 of each relay(thereby bypassing both relays) and see what happens. If that works, replace the fuel pump relay and then see what happens.
I have tried the jumpers between pin 87 and 30 on both relays, then the fuel pump runs all the time but boat still just cranks over with no spark
 

Trav2015

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I'm a Merc guy, but there are many similarities between Merc and VP. There are two relays on the motor, one is for main power relay (MPR) and the other is fuel pump. When you turn the key to ON you hear the fuel pump turn on. If this is the case remove the two relays and swap them with each other, they are both the same. Turn the key again and see if the pump turns on.

If this checks out, check for power on Red/Purple wire coming from the MPR with key ON. If you have power (12V), turn power off and remove connectors on ECM and see if they need cleaning. Do not reinstall connectors and check for 12V on R/P wire at ECM connector when key is turn back ON. If 12V is present, turn power OFF and reinstall connectors. Check grounds from ECM and from battery. If none of this helps need to see if there are any codes showing up by using a scanner

Hi there, I have performed these checks exactly! I'm getting 12v everyplace u asked me to test! Starting to think I need to test the ground side! Willing and open to ideas of where else to test! Thanks!!!
 
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