[Umbriel]

Originally Posted by gmcvt

I would think it has to be a sensor of some type?(pressue?) The pump is mechanical, not electrical.

This, it is a mechanical pump so it doesn't need power to turn on it so it is a sensor of some kind, most likely pressure or revolutions.

[s3rics213]

Originally Posted by Choda

If its the right pump then just plug it in and stop making the same thread in different sections. Obv we all think you somehow got a different pump because the connectors are different. Did you call the place you bought the pump from to see if there are different part numbers for a 2019 lt4 HPFP?

Instead of being a jackass understand that I stated everything above. And I posted in two locations to get more views. It’s like posting on Instagram and Facebook to get views on something else.

Yes the lt4 pump number hasn’t changed from 18 to 19-20 zl1. It’s the lt1 on the 19 that changed from the electrical. Even the dealership shows that the pumps completely changed on the lt1 and the lt4 stayed the same. So for the last time the lt4 pump I have is the correct pump.

If you can’t be of help and not dealt with it don’t respond. Possibly someone else has a fix due to there not being a different lt4 plug with out cutting up a harness.

And the current fix I am working on is getting the entire lt4 rh side fuel injector harness.

[s3rics213]

Originally Posted by Umbriel

This, it is a mechanical pump so it doesn't need power to turn on it so it is a sensor of some kind, most likely pressure or revolutions.

Should be to read the psi of the high side.

[Umbriel]

Maybe they changed the pumps on the 19+ cars and the LT4 pump is no longer a direct swap.

[oldman]

AFAIK, that connector is either a PSI sensor, or a variable relief valve. Probably the latter, but I don't know. I'm just going by tables available in the scanner and there is a PSI input and there is a demand table for the HPFP.

[s3rics213]

Originally Posted by Umbriel

Maybe they changed the pumps on the 19+ cars and the LT4 pump is no longer a direct swap.

Seems to be the case is that they don’t just swap over now. Working on either building a pigtail for ppl to know of on there 19 builds for later. Also getting a 18 harness and seeing if it’s just a harness swap also.

Originally Posted by oldman

AFAIK, that connector is either a PSI sensor, or a variable relief valve. Probably the latter, but I don't know. I'm just going by tables available in the scanner and there is a PSI input and there is a demand table for the HPFP.

Yeah seems to just be a sensor and I just want to be safe and have the right wire harness for it.

[NickeyMatt1LE]

Here's what I just took off a 2020 ZL1. Same part #. Different pump than what you have. Did you check the number on the the pump vs. the box?


Attachment 1025556


Attachment 1025557

[s3rics213]

Originally Posted by NickeyMatt1LE

Here's what I just took off a 2020 ZL1. Same part #. Different pump than what you have. Did you check the number on the the pump vs. the box?


Attachment 1025556


Attachment 1025557

This is the same pump I have. My lt1 pump has a different plug. The lt4 pump I have in the car now just not with a electrical plug in it is on 12694529
The first picture is my old pump and the second picture is the lt4 pump already installed in the car. The lt4 pump is the same as the one you posted.

[NickeyMatt1LE]

Originally Posted by s3rics213

This is the same pump I have. My lt1 pump has a different plug. The lt4 pump I have in the car now just not with a electrical plug in it is on 12694529
The first picture is my old pump and the second picture is the lt4 pump already installed in the car. The lt4 pump is the same as the one you posted.

Ahh. Got it. I was thinking the first pic was the new pump.

[s3rics213]

Originally Posted by NickeyMatt1LE

Ahh. Got it. I was thinking the first pic was the new pump.

But yeah that’s what I mean I the connectors are different. I did just order the harness off the zl1 so hopefully that works. Ik it will plug into the pump but more of if it will plug into the main engine harness

[TJay74]

While the pump is mechnical, the electrical sensor has to be plugged in for the pump to work otherwise it could go into bypass mode. The sensor provides the PSI which the ECM needs to know, but it can also open the bypass ports if the pressure is to high.

My guess is GM change the LT1 connectors and the LT4 connectors to keep people from being able to plug and plug the LT4 HPFP into a LT1 vehicle. So my guess if that is the case that either a adapter harness will be needed or the sensor on the HPFP will need to be swapped over.

[s3rics213]

Originally Posted by TJay74

While the pump is mechnical, the electrical sensor has to be plugged in for the pump to work otherwise it could go into bypass mode. The sensor provides the PSI which the ECM needs to know, but it can also open the bypass ports if the pressure is to high.

My guess is GM change the LT1 connectors and the LT4 connectors to keep people from being able to plug and plug the LT4 HPFP into a LT1 vehicle. So my guess if that is the case that either a adapter harness will be needed or the sensor on the HPFP will need to be swapped over.

Yeah exactly but the sensor doesn’t come off. And that’s wht I was trying to get at to see if anyone made a adapter or what everyone with a 19 or new has done. I’ll be going to the dealership here shortly to get a harness from a zl1 I ordered to see if it will be a swap. I’ll update once I figured it out.
Harness 12689504 will be a direct swap for harnesses for anyone with a 2019 trying to upgrade the hpfp to the lt4 pump.

[s3rics213]

Update

[ChadFarr]

Originally Posted by s3rics213

Update

nevermind. i see you updated it at the top. thanks