The test software (if this applies to the region) would read which OBD monitors are supported by the PCM, and which of those are Complete (aka set aka ready aka passed). Some regions allow 2 or 1 not to be, but many require all those supported to be complete (as well as no codes).

Currently it's a pathetic visual check of MIL here, with tailpipe gases tested.

 

Oh right.

The obdwiz software has "ready for emissions" or something like that and it is selectable by US state. Looking deeper behind the screen shows that there are varying sets of data for each state. Only useful in the US though.

 

That's quite cool. I think the # unset monitors depends not just on state but also on MY of car sometimes, and the average Joe really can't be expected to go digging in the laws and OBD data to figure it out.

There are different rules for larger vehicles, too.

 

The average Joe doesn't even have an ELM interface

Although, if the CarMD infomercials have their way, every Josephina will have one in their glovebox at the ready. If they can find it under all the accumulated trash

 

There must be a leak, have it smoked again! Try and do it on nearly empty tank of gas. In my experience smoke testing when done properly is a reliable test. The Cannister Close Valve has to be commanded closed with a scanner, and then watch the flow rate on the smoke machine gauge to gauge the size of the leak. (A 0.040 leak is significant). A bad cap will show up with smoke. If there is no flow then the purge valve becomes suspect (depending on how and where the smoke is being introduced). I believe your car has a port for testing.

Good luck!

 

Well I've received the new gas cap from the Jag dealer. I've installed it and reset the CEL. Fingers crossed.

 

If you cant find it in the glove box then try under that ginormous pile of stuffed animals sitting on the rear package shelf ...

 

It's been six weeks and 3k miles since I installed the new gas cap. To this point, no CEL. Somehow I feel I just jinxed myself.

 

haha, I know what you mean! Probably IS fixed, though and thanks for the follow-up.

 

Really happy to hear that!

 

Ahhhh...the first brave, bold step to DIY repair. First you crawl, then you walk, then you run. Bet you can almost feel your speed picking up already. Lol!