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Thanks guys.
My truck has 125K miles and has shut down on me a few times. The thing runs fantastic.... until it shuts off.
This happens when I get into it. Once while towing and climbing a mountain.
Computer hook-up shows low fuel pressure. We believe this thing will cure the problem for good.
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CP4's have a very low failure rate in Fords. Anything to the contrary you read is just forum experts regurgitating stuff they read online. I am a ford senior master and have done in total exactly 1 high pressure fuel system that could not be attributed to neglect and was actually covered by warranty.
The most common thing i see that shows low side fuel pressure is.
1. Homeboy changes his own fuel filters on the frame mounted era fuel pumps and doesnt get it tightened all the way because the threads are all packed with dirt.
2. Fuel system contamination. Usually def, sometimes water. It will cause pump failure or problems with the VCV or PCV and register as a low side system code but it usually has low/high cranking pressure codes associated with it as well.
3. Somone uses a fuel additive or cetane booster and the cardboard gasket from the lid gets stuck to the spout and they dump it in the fuel tank and clog the pickup. When they shut it down it drops away from the inlet and may go hundreds or even thousands of miles before it happens again.
4. A concern with the PCV or VCV. Usually the PCV because they are kind of finnicky to install.
5. An injector with a stuck open return.
Replacing a CP4 out of concern is pants on the head a waste of money.