Turbo actuator hacking.

[Hush]

Hello everyone. I have a issue with my engine harness. A few days ago I washed my engine, the truck wash sprayed it with acid and now it has messed up some wiring I can't find.

The issue is that the turbo actuator is opening and closing the vgt constantly. Won't let me drive. A barely get 8 psi boost.

I disconnected the harness to the turbo actuator and I am getting 17 psi. This was okay for the flats but tomorrow I have to drive through the Appalachians. I need more boost.

Heres my problem. There are four wires going to the turbo actuator, red, yellow, green and green with a white stripe.

I want to momentarily feed some current into the actuator so the vgt vanes get opened. Run it like an old school turbo.

Here's the thing? What kind of motor is in the actuator? Dc? Ac? Brushless? Or is it as solenoid? Is their spring in there?

Into which wires should I feed the current?
I am thinking if I momentarily energize the right wires the actuator will open up the turbo.

I know it can be done and the truck can be driven this way. About five years ago I had a vgt part of my turbo fail in the open position. I was able to drive it home over 4000 miles. Lol

I just needed to watch my egt temps and boost.

So if any of you guys know which wires to open the turbo please let me know. I desperately need to deliver this load. Afterwards I can go to a shop.

My other option is take the actuator out and manually adjust the turbo. But it's 21 outside and snowing and I am at a rest area.

The engine is 2008 cummins isx cm871.

Thank you.

[Rawze]

the turbo actuator operates on ...

RED Wire: +12volts To Power it up.
BLACK Wire: Ground connection.

YELLOW AND GREEN Wires: CAN-BUS High and LOW... J1939 network communications signal.

There is no "analog" settings, signals, or voltages for the turbo actuator at all. It is controlled via J!939 communications data at high speeds .. it is similar to transferring data to/from any other type of networked device.

BTW: Even internally... there motor inside it is also 3-phase stepper motor.. Again.. there is no "DC" or "AC" signal driving it. It is not nearly that simple like you are trying to make it out to be there.

if you have communications issues to the turbo actuator.. and it is wiring related then --- I suggest that you FIX THE PROBLEM!!!, Because that means that the whole J1939 network is on the fritz. That is bad for the whole engine, not just the turbo controller.

[Hush]

I see. It's a lot more complex than I thought

Thanks for the reply.

Going to try the delivery on 17 psi. Lol

As for the repairs. Hopefully after the delivery.

[Rawze]

(02-14-2022 )Hush Wrote:  I see. It's a lot more complex than I thought

Thanks for the reply.

Going to try the delivery on 17 psi. Lol

As for the repairs. Hopefully after the delivery.

- When my turbo failed on my own truck back in the day, I drove it all the way from California to Atlanta. I had no boost, but was bobtail, so I did not need much power for most of the trip. - It was terrible when I would hit a steep hill.. I would be down in low range .. but I eventually got it all the way home, so that I could fix it and take some time off.

My own truck is out on the roads to make and squeeze every single last red cent of money, every single mile, of every single day, while my truck is moving. Anything less than maximum profit long term is just simply Bulls%it to me hands down!. I have more than {now its 1.4} million miles on my equipment and have only ever purchased ONE turbocharger replacement for it in that time span, and at 1.3 million miles, while replacing one of the rear ends for the truck, I removed that turbo to have it gone thru just out of concern. It was still fully functional .. but I had YTS-turbo go thru it and replace any worn out parts. The actuator, I rebuild that myself.. have done it 2 times now, and have a video series on what I do to rebuild it.

Looking back at the very first turbo failure and why I replaced it, it actually was my own fault that it failed. I made the mistake of shutting the truck off with the turbo at 900+ degrees and it carbonized the bearing, back when the engine was still fairly new / about 200k miles on it. it did not get replaced however until it had 580k miles on it... because it was still operational. The reman that I replaced it with back then now has more than 820,000 miles on it at the moment and it is still going strong.

[Chamberpains]

(02-14-2022 )Hush Wrote:  I see. It's a lot more complex than I thought

Thanks for the reply.

Going to try the delivery on 17 psi. Lol

As for the repairs. Hopefully after the delivery.

Gear down and continue to gear down till 17 psi is all you need to pull the hill. I've been driving this way for 4 years in the Appalachians using rarely more than 20 psi mayne the occasional 22 psi.

Always remember, it's a business not a race. Getting there fast won't net you the most money. And in your case 17 psi will pull 80,000 lbs gross up any hill the Appalachians will throw at you. I've checked and verified that for you.

[Hush]

Just wanted to let everyone know I made the delivery. After some very slow mountain pulls (5 mph) the truck mysteriously started running just fine.

After the delivery I made it to a truck stop and inspected it thoroughly. I found a bunch of wires with worn-out insulation. There was at least 8 wires like that, coming out of the ecm.

Turns out the last shop forgot to put the plastic covers back on. The harness rubbed through against the charging wire.

Anyways, I cleaned and insulated everything. The truck has been running good with no issues since then.

So thank you evenryone for your suggestion and advice.