Brad Bilut

This is not a relation to an Audi, but my girlfriend called me today and said she lost her gas cap???? I asked her if her check engine light was on, she said no. I told her that it probably will come on. She drives a 99 Honda Civic, which I figured has an ODBII system or something similar. She called me later and told me her check engine light came on and she went to an auto parts store and got a new gas cap, but the light is still on. I wasn't really able to get an answer from the archives if the error code has to be reset from the computer by dealer or if it clears itself. It seemed like most people went to the dealer right away to have them clear code. Does anyone know if this will reset itself?<p>Thanks!<p>Brad Bilut 98 A4 2.8Qtip

DaveG

Regarding a missing gas cap, I do not kow how a Honda would react. However,<br>a 99 Volvo (V70 XC) and a new 98 Audi would trigger a check engine light if<br>the gas cap is not on tight enough or missing. Both are personal experiences. The Volvo was<br>my mom's and the Audi incident occured on a test drive (nice impression!) <br>I would assume that a Honda w/ OBDII would do exactly the same thing.<p>/Dave Gitlin<br>waiting for an S4 tip

David P

Hi Brad. I recall someone mentioning that the OBDII system will reset a fault if it doesn't see one for a certain number of start cycles. I'd bet it will go away in a day or two.<p>David

Peter Finch

A friend recently spent several hundred dollars to have the gas tank and fuel pump in his jeep replaced. He had lost his gas cap and bought a replacement at an auto parts store. Though listed as fitting his Jeep, it was unvented. The draw from the fuelpump collapsed his gas tank over time until the fuelpump itself was damaged and the tank ruptured. All this to save some time and money by getting a cheap cap at an auto parts store. He now displays the gas cap in his office as the $600 gas cap. I, personally, will pay extra if I ever need a gas cap to get the one the manufacturer intended.<br>

GaryJ

Agree.

RobJ

I had this fault occur, and the light switched off the next day...hope same happens for you.

Mike U.

Try starting or at least key the car on and off several times. That should clear it. I recently started on a module programming team, and I think the (major) auto company clears some OBDII faults like this. But don't hold me to it.<p>Mike U.

Mike Holder

Should take just a few trips of a few miles to clear the check engine light. See the URL below for more on the OBD II system.<ul><li><a href="http://members.aol.com/carpix256/library/us796obd.txt">Understanding OBD II</a></li></ul>