Charcoal cannister buzzing duration? (1 Viewer)

[BTLSHP]

Ok. So after drive. Turn off vehicle.. pop bonnet.. unplug hose on tank nipple off cannister.. see if I hear the puff of air there.. if not.. go to gas cap and remove and see if I hear it there instead.

Yes, now the way I checked my connection is with an adapter on my bicycle pump on the tank hose. I took the gas cap off and pumped a bit and found no pressure build up. Then with the cap on I pumped maybe 5-7 strokes -pressure gauge did not move but air came back out the hose.

My little check valve ball was varnished closed

 

[petegangies]

Update. Car barely runs now. Idle is all over the place and stalls if you try to drive it. Fuel in FPR vacuum line. Not sure if this is the sole cause or something else has s*** itself as well. Limped home today 30mins away. Stalled multiple times. So over this truck! New fuel reg on the way..then it's off to a mechanic and auto elec. I've done my 12 months of playing with it. Finally admitting defeat.

 

[CharlieS]

There shouldn't be fuel in the fpr vacuum line. The diaphragm in the fpr is likely ruptured. Pulling gas into the intake via that vacuum line (and associated vsv) seems like a pretty bad thing, messing up your fuel/air mixture.

 

[petegangies]

There shouldn't be fuel in the fpr vacuum line. The diaphragm in the fpr is likely ruptured. Pulling gas into the intake via that vacuum line (and associated vsv) seems like a pretty bad thing, messing up your fuel/air mixture.

Yep.. won't drive the car again till the FPR is changed. Hopefully haven't damaged the motor driving it for 45mins like that.

 

[petegangies]

There shouldn't be fuel in the fpr vacuum line. The diaphragm in the fpr is likely ruptured. Pulling gas into the intake via that vacuum line (and associated vsv) seems like a pretty bad thing, messing up your fuel/air mixture.

Replaced the FPR.. unfortunately it didn't make a difference. Car is still running super rough, erratic idle and stalling.

Here's my gas cap release:

 

[petegangies]

Replaced the FPR.. unfortunately it didn't make a difference. Car is still running super rough, erratic idle and stalling.

Here's my gas cap release:

I'm going to temporarily bypass the canister. I'll cap the line to the intake manifold and stick a little in line fuel filter on the tank line to vent.

That should tell me if a bad canister is causing my hard starts and poor idle/stalling issue. Will also see if tank cap has less pressure when opening..though without driving it may not build much pressure anyway.

 

[CharlieS]

I have done what you describe on trail when my charcoal canister failed. It works fine, just be aware that you might get gas fumes in the engine bay. It was a very hot summer day when I did this, so that may have contributed to the fume issue.

 

[COS80]

I just replaced my canister and it resolved the pressure issue, as well as a horrible stench that I thought was running rich. My tank hissed (pressure), although much worse than that. There was no buzzing. When I pulled the "to tank" line, it hissed for minutes. Mine ran beautifully, though, so you may have more going on than just the canister.

 

[petegangies]

I just replaced my canister and it resolved the pressure issue, as well as a horrible stench that I thought was running rich. My tank hissed (pressure), although much worse than that. There was no buzzing. When I pulled the "to tank" line, it hissed for minutes. Mine ran beautifully, though, so you may have more going on than just the canister.

for sure. I doubt my canister is the ultimate issue, but just trying to rule things out one by one. The buzzing might be pressure trying to be released in the canister? I've replaced the FPR, so that's brand new (genuine Denso)... next will be investigating the fuel pump (and filter), and the injectors. I suspect, there may be an electrical/wiring issue that's telling the injectors to work overtime, and flooding the motor. The car had a second hand wiring loom put in it a few years ago, and it's never run great since, in fact, it's gotten progressively worse. Car is off to a mechanic this weekend, I've exhausted my ability/knowledge, plus things are complicated when you factor in the LPG, and the electrical side of things (the LPG systems are spliced into the main wiring loom/ecm).

 

[petegangies]

I have done what you describe on trail when my charcoal canister failed. It works fine, just be aware that you might get gas fumes in the engine bay. It was a very hot summer day when I did this, so that may have contributed to the fume issue.

Yep, hopefully with that filter on the end of that line, I'll try and point it down toward the ground. I'm only going to start and idle it in the capark as a diagnostic, that should be enough to confirm if it's causing any issues. I dont feel like the woosh from the cap is excessive, but I also don't know what's considered "normal" for these cars. The buzzing at the canister is also weird, so it'll be interesting to see what this temporary by-pass does!

 

[petegangies]

by passed the charcoal canister yesterday and it made no difference to how the car is running. Given the car runs properly on LPG and not on petrol, I'm guessing that when the auto electrician replaced the wiring loom with a second hand one (not exact same loom), that something has been wired incorrectly, that is telling the injectors to constantly spray fuel. My symptoms are consistent with chronic overfuelling. It's off to the mechanics this weekend, he works at an auto electrical place so has that experience too. The LPG systems also splice into the ECM wires, so something could be off there too. I've done all I can from the mechanical side of things. Failing that, fuel pump, fuel filter or a leaking injector are all possibilities.