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Hi there, I've made a post in the past regarding lean long term trims on both banks I'm experiencing.
I've ruled out a lot of stuff and only have a couple to go before I've conclusively(ish) narrowed it to the intake manifold and feel ready to jump into that.
now to the question. I've replaced the purge valve hose (green connector) on this truck, but now need to confirm if the valve itself is shutting fully, as far as I can discern. I know I can do this with a hand vac pump, which I have, but if I'm confirming this, which hose connection am I testing for this?
My first assumption is that it'd be the port connecting to the throttle body itself, as this is where it would have to leak to cause a lean condition to begin with. Is this correct? The other port goes to the canister itself and I can't imagine an issue with that end causing lean trims as opposed to rich
I like to leave it connected to the intake vacuum source and put my vacuum gauge on the side of the valve that goes back to the canister.
With the the electrical connector unplugged and the engine running there should be no vacuum coming through the valve.
What Noah said. If your sole concern is a trim issue, then that test will give you positive go/no-go results. Any vacuum on the fuel tank side of the purge valve with the engine running (and the connector unplugged) is a failure.
Thank you guys for that! a question about the canister side of the valve being unplugged while running - are those vapors likely to escape out of that hose? Or is it safe to plug short term? Just looking to maximize safety and I haven't tried this before regarding the purge valve.
going to give this a shot this weekend. planning on doing the intake manifold/gasket anyway because they seem to be original and there's coolant leaking for sure. I have rust/ brown liquid on the walls of the #6 plug well, and can see coolant running down the engine valley slowly from about that area underneath. No wetness/liquid build up in there after removing the coil after driving it though, so I'm hoping everything is good there.
also will take me almost all the way to removing the valve covers to replace the valve cover gaskets. but I want to make sure I know what is and isn't working, regardless.
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