Have an 01 ram 1500 5.2 has a long crank but only once when I go to start cycling the key to build up fuel pressure seams to help a little sometimes has new sparkplugs and cables new starter and alternator I also have the 0445 code I’ve checked it out replaced some old cables from the charcoal box but code no go away I hooked up a pressure gauge and the pressure was at 55 , is it possible for the fuel pump to have a hard time starting but once the vechile has warmed up so has the fuel pump so then I starts/runs fine only long crank once?? I also I think maybe uses to much gas not 100%shure??? I’ve checked air filter already to???
If the key dance helps getting the engine started when it has sat for a while, usually points to a problem with the anti drain-back valve on the fuel pump assembly.
Ya I plan on changing the feul pump I was just wondering about the possible codes and why it seems to start fine after the the first start doesn’t have anything to do with the injectors ?
Your question was about the fuel pump.
The code indicates the purge control valve circuit is shorted.
That’s connected to the fuel pump correct
Would this affect mpg???
The way the gas fumes in the gas tank are handled to prevent them from polluting the air, they are stored in the charcoal canister; then when driving at moderate speeds the purge control valve is opened, which causes all the fumes in the canister to be drawn out of the canister and into the engine where they help to make the car go. i.e. the fumes are purged from the canister into the engine, which allows new fumes to be stored in the canister as needed.
The purge valve is only supposed to open when driving at moderate or above speeds. If it opens at idle or low speeds it can result in a too rich mixture, with resultant hard starting, poor idle performance, and stalling. So the first priority imo is to get the purge problem resolved, as that might solve your other symptoms.
The purge valve opens to draw the gas vapors from the charcoal canister when the engine is started cold.
The engine needs a rich fuel mixture when started cold anyway. So why not draw those gas vapors from the canister into the engine at that time?
“If your canister purge valve is stuck open, however, it creates a vacuum leak that can affect your engine adversely. Simply put, air will be allowed to enter the engine in a quantity that is not predicted by your car’s computer. This will change the car’s air to fuel ratio, and can cause rough idling (car feels rough and bouncy when the engine is running), as well as difficulty starting.”
But a purge valve is normally closed.
It only opens when the engine is started cold.
Unless it fails open. Which is what happened to my 05 gmc truck. However, I didn’t notice any performance difference after replacing it.
I don’t believe P0445 applies to this truck, are you sure it wasn’t P0443 or P0455?
I’d guess if the purge valve fails to open you might not notice anything other than a CEL. If it opens when it shouldn’t, seems like the driver would be more likely to notice that.
What I’m saying is mine failed in the open position. The little flap (or whatever’s inside) quit closing. I could blow air through the solenoid with no power going to it (and with 12 volts applied also). I didn’t notice anything other than the cel and the annoying “tighten gas cap” message. As far as idle quality, driveability, etc., I had no symptoms of a vacuum leak. Not sure why.
At least replacing the solenoid turned off the dash light and got rid of the blasted gas cap message!
With an engine this large it will go unnoticed if the purge solenoid is stuck open/closed or if the hoses are disconnected however those failures are monitored by the PCM.
Codes listed were 0463 0442 0455 I do believe
P0455 is a large evaporative emissions leak.
P0463 is fuel level sensor open circuit.
The fuel level sensor is part of the fuel pump module.