Review on ACDelco 19259325 Original Equipment Canister by Sam Bauer

I don't usually write positive or negative reviews, but this one left me "out in the cold". I bought a product with the AC Delco label to make sure I wasn't buying a one-size-fits-all product. This part was used to repair a large code P0455 EVAP leak due to exhaust valve failure in the vapor canister. Normally I would just replace the bleed valve and send it on its way. However, on the 2006 Cadillac AWD STS, the entire rear subframe that houses the vehicle's exhaust hanger must be removed to access the breather valve installed in the canister. I had no intention of installing a new valve in the old canister as there is a possibility of a problem with the canister and I will have to spend 4 hours removing the exhaust and subframe again. So the canister was replaced, the codes cleared and the exhaust valve was tested and working. The car was released. The customer returns with the vehicle after driving approximately 500 more miles and the check engine light comes on again. It now has a small leak of EVAP code P0442. We do a smoke test and come back empty. We run a vacuum test on the purge valve and find that it is not holding a vacuum. We replace the vent valve, erase the code and the vehicle is returned to the customer. Another 500 miles later, the customer returns the same code P0442 again. We run the smoke test again and don't see any leaks anywhere in the system. We are currently in the process of isolating every component in the EVAP system. This involves removing components and blocking certain lines to isolate the source of the leak. To access the top of the fuel tank on this vehicle the fuel tank must be removed which involves removing the transmission in addition to the rear subframe and exhaust system which must be removed. We insulate the wires and test them with smoke from the middle of the frame to the front of the car. No leaks. We insulate the wires from the middle to the back of the car. No leaks. The filler neck with the tank cap closed is isolated and checked. No leaks. The fuel tank is tested with an endoscope to inspect the top of the tank. No leaks. Every component we tested has been tested with no leaks. Only the gas cartridge remains. We insulate the newly purchased canister with a new vent valve. No smoke detected but the smoke machine gauge shows a 0.28mm leak, oddly no trace of smoke. Since the canister is pushed against the bottom of the vehicle and blocks 360-degree vision, we decide to remove the canister to take it to the cabin and do a smoke test. We remove the canister with all its external connections, including tank pressure. sensor and block all entrances and exits on the canister. We remove the exhaust valve and inspect the seals on it to make sure we're not dealing with a bad o-ring on the valve. We put a new one in just to make sure we have a properly working valve. We turn on the valve so it closes and install the smoke machine on the canister inlet. We open the inlet and outlet openings on the canister to let the smoke through. After seeing that the smoke comes out of each hole, we close the canister. After the canister is sealed we still have a 0.28mm leak on the gauge, but with a bright light around the entire canister and focused on each canister lid we still have no sign of smoke. I have completed many of these EVAPs. Repair and I have yet to have a case where there was a leak but no smoke to determine where the leak is. We buy another canister after the sale and do the same test. No smoke or leaks that would otherwise be detected with a smoke machine meter. Fine. Failures on new parts do occur, although not frequently. My problem is the 30 day guarantee on the canister I bought from Revain. It's possible that it's my fault for not checking the details here before ordering. I'm so used to having auto parts guaranteed for at least 1 year against manufacturer defects that I just assumed this was the case for this part as well. I was wrong.