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fuel vapor canister


pimtool

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Does the 2.9 rely on the fumes from the canister when the throttle is opened?

In other words, if the fuel tank is not vented to the canister will this cause the engine to run poorly when the throttle is opened quickly?

Can the the vacuum line that goes to the canister be removed and plugged?

Thanks.
 


RonD

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No reason to remove it.
An engine only has high vacuum at idle, when you open the throttle the vacuum drops.
So no it doesn't need to be hooked up for performance reasons.

The EVAP is to prevent evaporation of fuel in the tank, which on a warm day can be a lot depending on fuel level in tank.

The EVAP is also a smog control device so may be required in your state/town.

But yes you can unhook it, then get a vented gas cap to prevent an air lock in the tank, or run with gas cap a little loose.
Yes it will turn on the CEL if unhooked.
 

pimtool

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Thanks guys, if I pull the line off at the canister I can only feel vacuum when throttle is opened. I know the vent in the tank and I believe the line that goes to the tank are plugged. When I throttle the truck it misses like its starving for gas. I have replace just about everything under the hood and it still does this. If I pinch the return line the fuel pressure goes up to 60psi and it runs like a raped ape. I replaced the pump and pressure regulator twice, still the same.

Maybe I have a vacuum lock and its not getting enough fuel.

On a side note, I have to run the pump 4 times before it will even start.
 

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Fuel filter?

Under drivers seat in frame rail, $10


60psi is too high for the 30-40psi injectors so I would run some Seafoam in the tank to clean them up.
I would also clean the MAF(air flow sensor) this sets the fuel air mix along with the O2 sensors.

There could be a leak in the EVAP line, so when PCM opens the solenoid for the EVAP you get a vacuum leak, so a lean mix in the engine.
There should be a 12v solenoid between the vacuum source and the canister, this is opened and closed by the PCM.

Here is a thread on that:
http://www.therangerstation.com/forums/showthread.php?t=89253
 
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pimtool

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I have changed the filter a couple of times. There is no solenoid for the evap. ( that I can see). Just a vacuum line from throttle body to canister. It doesn't have a MAF, just MAP. I'm pretty sure the o2 is shot. That at least gives me a few things to look over.
Thanks again.
 

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Undo the gas cap and see if it improves.
 

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