How about just sending an alarm to you as you pull away letting you know that your gas cap is not attached. My Land Rover requires vacuum in the tank to run. Guess what happened to me about a year ago in New Jersey [where it is full serve only]. That's right the attendant forgot to put it back on. I had to be towed away from the GWB approach at rush hour. Not fun! RFID tag on the cap - small sensor in the car.

<font face="verdana" size="2">Good idea. I like it better because I am a creator of a palm program that many people worldwide use it for recording gas fills, maintenance, etc. Some times I think, it would be so cool if car could tell the program that I have filled up gas and automatically record or when is the time cleaning up filter or oil change or tire pressure check, instead of my entering it up. I think bluetooth or wi-fi can make it happen. Most of the PDAs these days have one or the other networking capabilities - it would be really cool if cars communicated with the PDAs directly.

I think adding bluetooth to a car would open a tremendous amount of opportunity to do some really cool stuff. To purchasing gas, going through tolls, paying for parking, security checking going over the US border, getting diagnostics for troubleshooting engine problems, GPS, and on and on....

This is a great idea, but RFID is only used for ID tags. It's a static (non-changeable) code used to identify an item and track it through a system of some kind or, as in the keyfob concept, identifiy yourself to a system. For the kind of interactive communication you're describing, you'd have to use bluetooth (as suggested by someone previously) or some other dynamic communication stream.

I like the idea, what if you took it a step further....have a computer in the car..kinda like a black box that would record what type of services have been done on it and when. An example; you go to the gas station and have an oil change...the computer would record when you had the change etc. If would also record repair work etc. This could be done through some kind of external link to the car's computer. It would have to be tamper proof. I came up with this idea because I have been looking for a used car lately...of course used car sales people will tell you anything...but what if you had a way where you could really know what has happened with the car and if it has been kept up.

as long as the idea is optional. only rich people would pay to have this in their car. most people would rather save the money or not want such scrutiny on their private property and lifestyle patterns. you'll start getting spam and junk mail from Gas stations as soon as your car is signed up for this. still, this is a convinient idea for someone willing to deal with the consequences.

Amazingly my car has an optional tire pressure montior which reports tire pressure to my console, as well as tells me when my oil is low and when to change my oil! Wow!

Vehicle self-diagnosis is a great idea, but shorten the range. If you mark the transmission spot, a mere couple millimeters is enough.

Put the transmission region in the well leading to the gas tank, and the sensor on the pump nozzle.

I agree with [Mike]; I'm not a fan of everything becoming wireless. A pump-to-tank interface would be ideal, with the console on the gas pump allowing you to diagnose your auto. There could be another interior link, such as to the radio (some radios can sense your odometer and tachometer) or to a USB port where a textfile can be sent. This should be optional.

I like the idea of having sensors on everything. Until it costs me to have it fixed. As long as the repair costs are cheap, good idea.

Looking back on my earlier comment, I realized that the fuel line would be the last place you want static discharge from interface contacts.

This is NOT a good idea and here's why: any RFID will respond with it's code upon interrogation. That's what they do. It would be so easy to build an interrogator, steal someone else's code, then put their car's number into your own interrogator and steal fuel in their name.

The reason RFID is great for inventories, etc, is because it's so simple. But there is really NO protection from stealing codes--you just interrogate them the same way the gas-pump would. There's no battery in a passive RFID (it doesn't even have a computer) so you can never change it's code--not like these new garage door openers or military RFID's that transmit a rolling code that changes every time.

I once designed an RFID fueling system for train locomotives, but only our own captive locomotives used it.

read under 'security concerns'--I don't want to be wrapping my tag in foil every time I get gas.

http://en.wikipedia.org/wiki/RFID