AFRs are bad

[methodwares]

yes, i've searched and found a thread with the same title, but it doesn't answer my question.... the tpots have been replaced and adjusted, the adaptives are with in a few %, the tpots are pretty much spot on, the lambdas seem fine...

i reset the codes and at idle the afrs go bad within 30 seconds. reading the docs, they monitor more than just the fueling, they also look at the fuel system and pressure and stuff. last week when i got home, fuel was leaking from the cap (tank was a touch over 3/4 full), according to the docs if the vent hose is not positioned right or the carbon can has liquid fuel in it then the afrs can trigger.

where is the carbon can and the vent hose?

thanks

[simonsparrow]

I think the carbon can is in the passenger side rear wheel arch......at least there is something 'canister-like' in there

[methodwares]

when driving home tonite, a notice a high pitch whine, i've heard it before and thought maybe the fuel pump was acting up, but it usually goes away quickly tonite it didn't so pop the boot and it was actually a hissing sound from the petrol cap. the cork gasket looks like it had better days, so i'm guessing its not getting a good tight seal. wonder if that could cause the problem as there would be a pressure drop in the return line.

[alderley]

On my cerb, the cannister in the rear passenger side behind the wheel is my fuel filter. As you look into the arch it is on your right.

[spend]

Most cars now have tanks vented through carbon filter, and excess drawn into plenum by activating purge valve. Chim has standard LR units installed just behind front headlight undertray/wheelarch area. Tank vent pipe runs all the way from the tank down the passenger side chassis rail, across / under rad to cannister. Purge pipe runs from plenum to inner wing drivers side and down to front of wheel arch.

All the units I've seen are LR ones (actually GM parts) the later style with clip on purge valve are also commonly used on Rover 200/400s and can be picked up for next to 0.

Not sure if the same is true of Cerb, but nearly all cars I've seen have a similar setup, just some have separate purge valves, some have integral.

HTH, Dave