Check engine light- engine electronics stupid reason(gas cap open)?
Thread Starter
Member
Joined: Sep 2002
Posts: 235
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From: NY
2003 s500 sport
Check engine light- engine electronics stupid reason(gas cap open)?
Well you think that it would never happen to you but I was a little absent minded yesterday and after I got fuel I forgat to close the gas cap on my 98 e430.
My niece noticed it and just closed the door without telling me. Later like a half hour all of the sudden the check engine light comes on and I am like what the hell! in the middle of park ave in Manhattan. The car runs perfect though. A little puzzeled my girlfriend just threw an idea If I closed the gas cap. I would never think of that being the problem.
I opened the gas cap door and the cap was nicely tucked inthe holder but not on the hole. After I closed it I decided to complete the 70mile jurney I had ahaed of me and today the check engine light was gone.
Can someone tell me why would this trigger the check engine error?
Unless this is not related should I go have it checked out.
The error is now gone and the car runs like it did. Perfect!
My niece noticed it and just closed the door without telling me. Later like a half hour all of the sudden the check engine light comes on and I am like what the hell! in the middle of park ave in Manhattan. The car runs perfect though. A little puzzeled my girlfriend just threw an idea If I closed the gas cap. I would never think of that being the problem.
I opened the gas cap door and the cap was nicely tucked inthe holder but not on the hole. After I closed it I decided to complete the 70mile jurney I had ahaed of me and today the check engine light was gone.
Can someone tell me why would this trigger the check engine error?
Unless this is not related should I go have it checked out.
The error is now gone and the car runs like it did. Perfect!
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Joined: Nov 2001
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From: Bloomington, IN
1997 Toyota Tacoma 4x4
It's an emissions reason. By leaving the gas cap open, you're allowing fuel vapors to escape into the atmosphere instead of collecting in the charcoal canister, a huge no-no.
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Joined: Mar 2002
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From: Arizona, USA
W205 C300
Thank you girl friend
A lot of repair shops have made a lot of money off of that same fault. The gas cap seal is an emission standard to check for and will flag the CE light until the fault is corrected. A shop will tell you that your MAF (mass air flow) sensor is bad and charge you $400 to swap it and then replace the gasket on the gas cap. After driving for about 50 miles the code will clear or they clear it with a OBDII code scanner. Thank your girl friend for thinking of the gas cap...
Thread Starter
Member
Joined: Sep 2002
Posts: 235
Likes: 0
From: NY
2003 s500 sport
Yeah I did thank her 
But also thought what a cool way for dealers to make money. After I realised that the open cap was probably a problem I drove again and the code cleared by next morning.
thanks
But also thought what a cool way for dealers to make money. After I realised that the open cap was probably a problem I drove again and the code cleared by next morning.
thanks
MBWorld Fanatic!
Joined: Nov 2001
Posts: 2,332
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From: Bloomington, IN
1997 Toyota Tacoma 4x4
Re: Thank you girl friend
Originally posted by E-Klasse
A shop will tell you that your MAF (mass air flow) sensor is bad and charge you $400 to swap it and then replace the gasket on the gas cap
A shop will tell you that your MAF (mass air flow) sensor is bad and charge you $400 to swap it and then replace the gasket on the gas cap
MBWorld Fanatic!
Joined: Oct 2002
Posts: 1,560
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From: Columbia, SC
E300
Re: Thank you girl friend
Originally posted by E-Klasse
A lot of repair shops have made a lot of money off of that same fault. The gas cap seal is an emission standard to check for and will flag the CE light until the fault is corrected. A shop will tell you that your MAF (mass air flow) sensor is bad and charge you $400 to swap it and then replace the gasket on the gas cap. After driving for about 50 miles the code will clear or they clear it with a OBDII code scanner. Thank your girl friend for thinking of the gas cap...
A lot of repair shops have made a lot of money off of that same fault. The gas cap seal is an emission standard to check for and will flag the CE light until the fault is corrected. A shop will tell you that your MAF (mass air flow) sensor is bad and charge you $400 to swap it and then replace the gasket on the gas cap. After driving for about 50 miles the code will clear or they clear it with a OBDII code scanner. Thank your girl friend for thinking of the gas cap...
I had that this past winter in my dies... Mind you it was 15-18 degrees Farenheit :-) After about 100 miles the "check engine" went......
