19 Lt1 Swapped vehicle No throttle response

[Flipper7]

Hello I have a vehicle in the shop that has a 19 Lt swap A10 trans. Vehicle was brought in with engine and trans installed with a companies swap harness. Vehicle will start but no throttle plate movement when commanded from the Accel pedal. I can raise the Idle and it will move the throttle plate from ecm, but not pedal. When logging, I can see Accel pedal % move up and down, but once the engine is running, the Accel pedal no longer shows % movement. Attached is 2 log and the base file.

[GHuggins]

Who made the harness? You have a lot of codes you might want to look into. Torque is way too high too.

[Flipper7]

Bp Automotive is the harness manufacturer. This is a supposedly stock read. I contacted Bp about the codes, they said that all of the "permanant" codes will always be there, and to only address the "pending" codes.

[GHuggins]

You shouldn't have any codes unless something's wrong. Swaptime does the best harnesses and module setups for swaps I've seen and dealt with.

[Flipper7]

Okay, I'll look into the laundry list of codes. Thank you!

[Flipper7]

Also, the high side fuel pressure is reading max 95,000 and the lowside is reading 0psi. It appears there is a lot going wrong. Swap was installed by another shop, but it looks mostly just plug and play other than the ground, 12v constant and 12v ignition leads.

[GHuggins]

It's possible they hooked up the high side pressure connector wrong. There's two connectors there that are the same around the hpfp, but you should have some very specific codes for those and I don't think it'll fire at all if they're wrong, but don't remember 100%. Plus depending on the year model there is one specific power wire that's different on the 14 to 19 model breakpoints. This is why I like swap time's harnesses. He goes into detail to make sure everything is there and right so they're right once installed for the OS and modules being used. There's even different speed sensor connectors/configs depending on the 8sp being used, which you have a 10sp so no worries there.

[Flipper7]

I have heard of people getting the fuel injector harness inverted from bank 1 and bank 2. Bank 1 has the High side fuel pressure sensor input. I even tried inverting those just to test, even though they are labeled bank 1 and bank 2, but no dice on getting High side or low side fuel pressure readings. I thought maybe if there was incorrect high and low side readings, that maybe the ecm could inhibit throttle operation. But that is just a guess at this point,

[Camaro6]

You have the wrong fuel rail on the vehicle? You cannot swap rails from 16 to a 17 or 18, and 19+ are different as well. You can physically plug the drivers side harness into the engine harness but it's wrong. You would need the proper injector harness and sensor for what ever vehicle the ecm is written for. I've fixed this issue many times as people think just because it plugs in, that it should work. Fixed this 95,000 high side psi issue again last week for another guy. There are 3 wire and 4 wire pressure sensors. Let me know if that fixes the issue.

[GHuggins]

That's what I was remembering on the harnesses ^^^^ Although I thought for some reason they wouldn't crank if you did that and then I figured the 4pin sensor should have already been wired correctly for. Another reason I like the swap time harnesses - all of this is taken care of

[Camaro6]

That's what I was remembering on the harnesses ^^^^ Although I thought for some reason they wouldn't crank if you did that and then I figured the 4pin sensor should have already been wired correctly for. Another reason I like the swap time harnesses - all of this is taken care of

It will crank and run, but go into limp mode making it run poorly. Injector harness has pins different at the engine harness on some. Ecm simply thinks it has a sensor error, but nothing more than that. Car came in with 2016 fuel rail on a 2018 last week. We pulled the sensor and wiring from a 2018 and put it on the car. Car ran great after that.

I had a 2019 in the shop from another shop year or so back and same thing. They bought LT4 injectors that came with rails, but they were from a 17 or 18. Laziness was to install it as is vs putting the injectors into the fuel rail from the vehicle. I want to say the sensor looked the same but was different. Wire harness and sensor fixed that one as well. I've had 6 of these and if I see that high psi, I go right to it. All vehicles started and ran, but ran crappy and in limp mode. All things that look equal are not equal, lol

[Flipper7]

You have the wrong fuel rail on the vehicle? You cannot swap rails from 16 to a 17 or 18, and 19+ are different as well. You can physically plug the drivers side harness into the engine harness but it's wrong. You would need the proper injector harness and sensor for what ever vehicle the ecm is written for. I've fixed this issue many times as people think just because it plugs in, that it should work. Fixed this 95,000 high side psi issue again last week for another guy. There are 3 wire and 4 wire pressure sensors. Let me know if that fixes the issue.

According to the shop that installed the engine and harness, it is all stock, other than the Bp harness. Stock engine and trans from a 19 Camaro SS. Do you think the harness company could have made the harness for a non 2019 Camaro? It is a 3 pin High side sensor. I will ask the previous shop, if by chance the fuel rails could have come from another car. Thank you guys for the input! I really appreciate it.

[GHuggins]

I just about guarantee that harness company doesn't know there are changes between the years and just sends one out

[Flipper7]

I'm feeling the same. I'll call them Monday and ask them, I'll let you guys know what they say. Thank you guys for the input.

[Flipper7]

It will crank and run, but go into limp mode making it run poorly. Injector harness has pins different at the engine harness on some. Ecm simply thinks it has a sensor error, but nothing more than that. Car came in with 2016 fuel rail on a 2018 last week. We pulled the sensor and wiring from a 2018 and put it on the car. Car ran great after that.

I had a 2019 in the shop from another shop year or so back and same thing. They bought LT4 injectors that came with rails, but they were from a 17 or 18. Laziness was to install it as is vs putting the injectors into the fuel rail from the vehicle. I want to say the sensor looked the same but was different. Wire harness and sensor fixed that one as well. I've had 6 of these and if I see that high psi, I go right to it. All vehicles started and ran, but ran crappy and in limp mode. All things that look equal are not equal, lol

Is it just the fuel injector harness that is different? I'm gonna call the harness manufacturer Monday.

[Flipper7]

So on their website, this harness is suspended from orders till further notice.......

[Camaro6]

I call BINGO