Well,
I've been able to pass the CA smog tests the last three times...barely. All indicators showed my Cat was going bad. Not too shabby for lasting 480k on the 740.
I replaced my old one with a new, CA approved magnaflow Cat and my results were amazing for all three components. However, my fuel evap test failed.

I found my front rubber line to the canister cracked and thought that might be the issue. Nope, I put my vacuum tester on it and still no good. The fuel cap was tested at the test center and was good.

I see where others have posted, the front or rear rubber lines crack, knowing the major portion of that line is plastic. I plan on raising up the car today to try and replace the rear rubber line above the fuel tank. The tank vent line has a short rubber section too, but it's good.

Any others have this issue and what did they diagnose?

Thanks.

 

More then likely it is probably your filler neck out of round. I had to shape mine with some large pliers and it passed.
That was after I did the smoke test to find the leak in the system.

Look if you filler neck where the cap sits is round.

 

Get it smoke tested and they'll find the problem.

 

+1. Those necks do get stretched out of round as people press down on the gas pump hose handle, and after all these miles...

 

mine isn't stretched, there's a notch worn in it where the fuel filler nozzle rests when fueling.

 

Here in Oregon, one of two states (the other being New Jersey), it is illegal to pump your own gas, so one is helpless to manage how attendants handle the gas dispensing. I have seen many just rest their body weight, lean into the car, etc. Also, the fragile Volvo gas door gets manhandled and this results in them getting broken before their time... It is nice to have your gas pumped but I'd still prefer to be able to handle my own.

 

I had the lines under the car going to/from the rollover valve crack and break. Easily replaced with line from LAPS. The ovalized filler pipe also was an issue; careful bending with channellocks fixed it. But I also had some tiny cracks in the tube where the gas spout gets banged into that were very hard to see; some JB weld around them worked long enough to pass the test. I hear there is a marine grade JB weld that is fuel resistant, I'll use that next time. Replacement filler pipes for 240's are worth their weight in gold; don't know about 740's and 940's. Anything you can do to save your current one is probably worthwhile.