I got a engine light and code p0628. From what I have read usually means time for a new lift pump. I have no fuel pressure gauge at this time. Pump runs, truck runs good. Anyone had this because of clogged filters?

 

Finally got the correct filter and water separator still have the engine light and code 0628. Pump runs fine.Any ideas

 

You have minimal details in your post which is why no responses.


That code is directly related to your low pressure lift pump.
Without an in-cab fuel pressure gauge you actually have no idea if the lift pump is working properly.

What type of lift pump do you have? What year truck? What mods? etc, etc, etc.. Perhaps create a signature for your profile..

 

Thanks for the heads up. Didn't realize my signature was not posting . I am currently looking at gauge options hoping I can get it fixed in the mean time. My OBD 2 scanner only pulls the p0628 code but noticed today by cycling the key I have three codes 0633, 0243, 0628. 0633 is related to the key so not worried about that one. 0243 is related to waste gate solenoid malfunction. Is it possible 0628 has been there all along because of the fass pump and my problem is the waste gate solenoid? Or forget about trying to solve any of this till I get gauges?

 

I recommend that you install a quality in-cab low side fuel pressure gauge. It will help you with your current issue and will pay dividends down the road.

How is your external Fass pump wired in? Is the factory lift pump connector from the ECM connected to a relay to trigger the Fass?
Or is the Fass wired independently?
The 0628 code is the ECM not seeing the correct voltage or load from the lift pump connection. It is not from low lift pump fuel pressure.
There is no low side fuel pressure sensor on these trucks.

As for your 0243 turbo wastegate solenoid malfunction.. You did not post what turbo you have...
If you have the stock 2004.5 turbo, there will be an electrically controlled wastegate solenoid on the compressor side of the turbo.
It is a black cylindrical device with a connector hanging off it.
Make sure it's connected.

If you have an aftermarket turbo, it will not have this electric wastegate on the turbo.
Look for the connection from the ECU to the solenoid. Is there anything plugged into it.

If you have the stock turbo and the electric wastegate has failed you are likely overboosting which can damage the turbo.
An in-cab boost gauge will help diagnose any turbo boost issues and is well worth it also.

Quality gauges should be on your priority list. Other gauges to consider for your manual trans truck would be a high side rail pressure gauge.
The in-dash oil pressure gauge in this truck is fake. A real oil pressure gauge is also well worth it.
There was just a thread where a guy was having engine problems, believed the in-dash oil pressure gauge and is now shopping for a new short block.


Edit:

Here is a picture of the stock 2004.5-2007 5.9L HE351 turbo in the background with the black electrical wastegate solenoid installed.
In the foreground is a SS HTT turbo.

 

I have the stock turbo still. I will look into where this actuator is and see what I find. Going to try and order some gauges this weekend or maybe a Edge module. Thanks!!

 

Be advised that the high pressure pump can supply sufficient vacuum at its intake to draw fuel from the tank, but not well. Without adequate supply at the high pressure pump inlet, the high pressure pump WILL fail and that is a bill you really don't want to pay. Stop driving the truck immediately until you sort this out!

 

Finally got my gauges in. Fuel pressure is at a constant 16 psi so that is good. Boost is at 5 psi under easy acceleration and 25-30 psi if I get on it. This seams reasonable right?