Illumination of the Check Engine Light can be caused by a loose or worn gas cap.Google+
Car Problem Reports
Chevrolet Tahoe Check Engine Light Due to Gas Cap Issue
Chevrolet Tahoe Problem
Average Mileage: 104,944 mi (18,000 mi - 243,336 mi)
Visitor, 2002 Chevrolet Tahoe
Gas cap was lose
Visitor, 2006 Chevrolet Tahoe, 112,000 mi
I had this problem for over a year. Dealer "fixed" it for two weeks and $700. After being entirely frustrated I put it up on ramps myself and took a look underneath the rear of the car by the gas tank. Sure enough a hose was unplugged, I cleaned the oring in the fitting and snapped it back together. Problem fixed. NO $$$
check engine came on and I went to my local O'reilly's and used there machine to diagnosis the problem. The issues was resolves after I took my Tahoe to the dealership to get repaired.
Visitor, 2005 Chevrolet Tahoe, 60,000 mi
OMG, on going gas cap problem and engine light is going on. Way to expensive to pay a company to check the light and make the light go off. Really we need to buy a chip every time at $400. Any cheaper way to get this done??
Please give me ideas.......
Visitor, 2003 Chevrolet Tahoe, 243,336 mi
check engine light stays on. Throws four codes
YOu can tighten the gas cap and it goes away--this is the 3rd gas cap we've replaced.
Visitor, 2004 Chevrolet Tahoe, 86,000 mi
Engine light on due to gas cap issue but we have not been able to fix it, switch cap several times, problem continues.
Visitor, 2006 Chevrolet Tahoe, 75,000 mi
my i just unhooked light came on an the sensor throwing the code to get light off