My 07.5 lmm with dual cp3s is having a rail pressure problem. It will run at 10k at idle when ecm os asking for 5k. I have replaced valley cp3 Cp3 controller fpr on belt pump checked lift pump pressure checked return lines and changed tuning with no fix. However if i take the belt off the truck goes back to normal. Does anyone have any pointers to try anything else. If someone gets me an answer ill paypal them 200 bucks.
Need help
- Thread starter Toner619
- Start date
Dan clarke tuning.
It was good for a while then had issues. Thats when i changed valley cp3 to 10mm and then everything was good for a couple weeks and now same problem again. When i start the tuck in the morning no limp mode shut it off and start again its back in limp mode
It was good for a while then had issues. Thats when i changed valley cp3 to 10mm and then everything was good for a couple weeks and now same problem again. When i start the tuck in the morning no limp mode shut it off and start again its back in limp mode
If that 10mm pump is from Exergy, it most likely needs an adjustment to table B1015. In the last year or so, the exergy regulators have changed and need some massaging to the Desired flow current table to bring it back in the correct range at idle. Does the rail pressure come back in line with desired, when rpms come up a bit? If so, tuning change to B1015 should fix the problem. I have worked with the Exergy engineers on this table as i was seeing more and more of this a while ago with customers running the newer pumps.
Did u tell dan your issue? He may just need to adjust regulator current if this issue is only at idle. When you bring up rpm does the rail psi even out?
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