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Require some BMW help

jlaird

Great Pumpkin
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Granddaughter left gas tank cap loose. 1978 318
TI, caused the check engine lite to come on. How the heck do I get it to go off. Manual says go to dealer, seems a pain.
 
try disconnecting the battery for about 5-10 minutes.
 
I can see you need to get on ebay & buy one of those little reset gizmo's....go to dealer & pay the $50...oh, & tell her to not try filling it up with engine running either (don't ask how my wife found that out or what it cost to have a roll back take her Benz to the dealer).
 
Some vehicles are set so it goes off after 4-5 full tanks. You might try that first before spending any $.
 
Jack:

The computer probably needs reset, the tool is available from a company I can't remember but will post the info when I get home for a little over $100.

Either get used to the light being on or buy the reset tool, because it will cost you a bundle to get the car to the dealer each time the light comes on. The shop rate here is about $120 per hour. I truly believe that they made it possible for the service light to come on as often as possible on these cars.

Patrick
 
Jack

Try BMP design @ bmpdesign.com or 800 648 7278

Patrick
 
Jack - does her BMW have the little set of green - amber - red lights on the dash that signal when a dealer service is due? If so, you really want that tool.
 
It's things like that that make me want to drive my older cars more.

- Doug
 
[ QUOTE ]
It's things like that that make me want to drive my older cars more.

[/ QUOTE ]

Yup. Makes me stay away from anything newer than '68 "normal" cars. Commonly that light is called "the MONEY light"!

...and I used to WORK for a BMW dealership...
 
In 1978, leaving the cap off could not set a code; that did not happen until OBDII (on board diagnostics, version 2) cars were introduced in 2005. So you'll still want to understand why the light came on. BMW in those years, as Triumph and other manufacturers did, keyed the light into mileage, so that may be your only issue.
 
[ QUOTE ]
In 1978, leaving the cap off could not set a code; that did not happen until OBDII (on board diagnostics, version 2) cars were introduced in 2005. So you'll still want to understand why the light came on. BMW in those years, as Triumph and other manufacturers did, keyed the light into mileage, so that may be your only issue.

[/ QUOTE ]
Your right, but OBDII was mandated in 96. All cars sold in the US since then have OBDII. Evaporative emissions systems have changed quite a bit in that time though. For instance, on Toyotas a loose gas cap will set a check engine light, but filling the tank while the engine is running will not.
The computer needs a set of requirements to be present before it will run the test that will determine if the check engine light will come on or not. One of those requirements is that the speed sensors must see that the vehicle is moving (I can't remember how fast right now) That is there so that the light won't trip while filling the tank.
I'm 99% positive that even BMW diden't have electronically monitored evaporative emissions in 78. That's either a service light, or if it is a check engine light it's got to be for somthing with the engine itsself. like a mass air flow sensor, or an O2 sensor if the car has EFI.
 
[ QUOTE ]

Your right, but OBDII was mandated in 96.

[/ QUOTE ]

Oops, it was '96. I used to teach the stuff and retired from Nissan in '97. Just got my decades mixed up.
 
Thanks guys, was a bit concerned. Light went off by its self. Hehe, guess it was not too important.
 
The OBDII system will reset a check engine light for minor issues if the fault doesn't recur after several drive cycles. I suspect that's what happened.
 
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