Ever since I got this truck about 2 months ago after it was in storage for 4 1/2 years, there has been this buzzing noice coming from the charcoal canister when it is parked (and maybe when it is running too). When I pull the foremost front hose (that goes to the fuel tank, I think), the noisee stops immediately. It's a rythmic buzz, like a vacuum pump. Is it time to replace the canister, or is there some other maintenance (or lubrication) I can do? Thanks.

Sounds like a clogged line from the tank to the canister. Possibly even a bad gas cap. Are there any codes stored in the computer? Is the light on? I do believe there is actually a check valve in the system as well. If I get some time tomorrow I'll do some research on it for ya.

Thanks, John, I'd appreciate that. I don't have a meter to read the codes, yet. There are no other symptoms or indicator lights. Just this rythmic buzz that lasts for about 1 second every 10 seconds. It is not all the time, but most of the time while the truck is parked. Thanks.

I too have the same issue with my truck as well. It sounds like a rhythmic bumble bee noise. I was curious to see what this could be. The person that I purchased the truck said that it had been doing this almost since its original purchase date back in 1996?

O.K. guys, the charcoal canister is equipped with a check valve that incorporates two check balls. Depending on the running conditions and the pressure in the fuel tank, the check balls open and close the passageways to the throttle body and fuel tank. The book says that poor idle, stalling, and poor drivability can be caused by an inop check valve, a damaged canister, split or cracked hoses or hoses connected to wrong fittings. My guess is a clogged canister filter or a sticking check valve, both of which are internal to the canister, is the source of your buzzing noise. I can find no info on repairing the canister, and I believe it is a sealed unit. The book says to replace if defective or clogged. Hope this info helps.........

I also have a 96 that makes a buzzing noise from under the hood. It seems to come from the vacume above the drivers side fender well. Doesnt seem to affect the truck though, but like all the others any info on what it is would be great

HA I HAD A 96 TACOMA TOO AND IT MAD E THE SAME NOISE. I NEVER FIGURED IT OUT BUT IT ALSO NEVER CAUSED ANY PROBLEMS <img src="/forums/images/graemlins/confused.gif" alt="" />

my 02 taco has done it since day 1 new. I think it may be normal because i have no problems either.

Solution

Jason B posted in the 4runner forum about this charcoal canister as a recall issue. Please read. <img src="/forums/images/graemlins/kewl.gif" alt="" />

Josh is the shiznit! Good info.