Standalone Ls1 with LQ4 ECM
Thread Starter
Staging Lane
Joined: Aug 2010
Posts: 89
Likes: 0
From: Calhoun Ga
Standalone Ls1 with LQ4 ECM Im wanting to run a ls1 5.7 aluminum block in a Jetboat with an LQ4 intake with the truck harness.
My main question is about the fueling. This intake has the return lines on it. so does the ECM modulate the pump for the PSI?
I would like to run one line to the fuel lines because that is how the tanks are on the boat.
Also what needs to be done in the ECM to delete the BCM?
I have JET DST and will just send it out for a mail tune if its to much for that program. I have the harness with the fuse blocks but 2 connectors are unplugged. Im thinking BCM and OBDII?
How is the 99 LQ4 ECM setup for fueling? Modulate or pump is wide open and regulated down to 58PSI.
I was looking at the MSD inline pump with the regulator/ filter.
Help is much appreciated.
My main question is about the fueling. This intake has the return lines on it. so does the ECM modulate the pump for the PSI?
I would like to run one line to the fuel lines because that is how the tanks are on the boat.
Also what needs to be done in the ECM to delete the BCM?
I have JET DST and will just send it out for a mail tune if its to much for that program. I have the harness with the fuse blocks but 2 connectors are unplugged. Im thinking BCM and OBDII?
How is the 99 LQ4 ECM setup for fueling? Modulate or pump is wide open and regulated down to 58PSI.
I was looking at the MSD inline pump with the regulator/ filter.
Help is much appreciated.
Answers are in red
Im wanting to run a ls1 5.7 aluminum block in a Jetboat with an LQ4 intake with the truck harness.
My main question is about the fueling. This intake has the return lines on it. so does the ECM modulate the pump for the PSI?
No
I would like to run one line to the fuel lines because that is how the tanks are on the boat.
If you can't use a return system, you need to use a rail from a 03-06 truck, they are returnless. However, you need to regulate the pressure inside the tank (like 98-02 F-body or 03-06 trucks)
Also what needs to be done in the ECM to delete the BCM?
Nothing, just delete from the harness anything not needed and disable the DTC's that will pop.
I have JET DST and will just send it out for a mail tune if its to much for that program.
You can do everything you need with Jet DST
I have the harness with the fuse blocks but 2 connectors are unplugged. Im thinking BCM and OBDII?
If you mean the white and black connectors, both go inside the passenger compartment. They are for BCM, Instrument cluster, OBD2 plug and a few other things. Those connectors also have other wires you may need, like tach, OBD2 plug, MIL light and a few more
How is the 99 LQ4 ECM setup for fueling? Modulate or pump is wide open and regulated down to 58PSI.
The pump runs at full speed all the time, the PCM has no control over it. The fuel rail has a regulator which returns excess fuel to the tank to control pressure to 58 psi at idle with vacuum reference
I was looking at the MSD inline pump with the regulator/ filter.
Be aware that external inline pumps are for return systems, they rely on fuel flow for cooling. If you install a external pump to a returnless system it will burn in a few minutes. I don't know if a external pump for returnless systems exists
Help is much appreciated.
My main question is about the fueling. This intake has the return lines on it. so does the ECM modulate the pump for the PSI?
No
I would like to run one line to the fuel lines because that is how the tanks are on the boat.
If you can't use a return system, you need to use a rail from a 03-06 truck, they are returnless. However, you need to regulate the pressure inside the tank (like 98-02 F-body or 03-06 trucks)
Also what needs to be done in the ECM to delete the BCM?
Nothing, just delete from the harness anything not needed and disable the DTC's that will pop.
I have JET DST and will just send it out for a mail tune if its to much for that program.
You can do everything you need with Jet DST
I have the harness with the fuse blocks but 2 connectors are unplugged. Im thinking BCM and OBDII?
If you mean the white and black connectors, both go inside the passenger compartment. They are for BCM, Instrument cluster, OBD2 plug and a few other things. Those connectors also have other wires you may need, like tach, OBD2 plug, MIL light and a few more
How is the 99 LQ4 ECM setup for fueling? Modulate or pump is wide open and regulated down to 58PSI.
The pump runs at full speed all the time, the PCM has no control over it. The fuel rail has a regulator which returns excess fuel to the tank to control pressure to 58 psi at idle with vacuum reference
I was looking at the MSD inline pump with the regulator/ filter.
Be aware that external inline pumps are for return systems, they rely on fuel flow for cooling. If you install a external pump to a returnless system it will burn in a few minutes. I don't know if a external pump for returnless systems exists
Help is much appreciated.
Thread Starter
Staging Lane
Joined: Aug 2010
Posts: 89
Likes: 0
From: Calhoun Ga
Thanks Men.
I redone my harness last night and this is starting to look a little more cut and dry.
Im just gonna run a return line to the fuel tanks and turn off every MIL light that has any thing to do with drive train and emissions.
The regulator is built in to the fuel lines right?
So im looking at 500$ from having this project finished.
I redone my harness last night and this is starting to look a little more cut and dry.
Im just gonna run a return line to the fuel tanks and turn off every MIL light that has any thing to do with drive train and emissions.
The regulator is built in to the fuel lines right?
So im looking at 500$ from having this project finished.
