Check Engine Light Due to Gas Cap Issue on Chevrolet Trailblazer

Illumination of the Check Engine Light can be caused by a loose or worn gas cap.

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Average mileage: 93,915 (9,998–221,000)
8 model years affected: 2002, 2003, 2004, 2005, more2006, 2007, 2008, 2009
128 people reported this problem
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problem details
2007 Chevrolet Trailblazer 52,746 mi,
I have replaced the gas cap and it still does it at times. I am not convinced that the problem is in the cap, perhaps it is in the sealing surface of the tank neck.
2007 Chevrolet Trailblazer 105,000 mi,
Have same promblem tighten gas cap and good ole service engine light comes on. Replaced 3 caps already. My next stop was to replace filler neck. Any suggestions or has anybody fixed there promblem yet?
2005 Chevrolet Trailblazer 75,000 mi,
I have replaced the gas cap I cannot even remember how many times, same problem, check engine light on. My mechanic told me it has always been a problem with the Trailblazer, ignore it he Why hasn't Chevy recalled this and solve everyones problem!
2007 Chevrolet Trailblazer 111,000 mi,
stupuid freaking engine light on!! got the tighten fuel cap message first, then poof! the lovely engine light! replaced gas cap, had light shut off, only to go back on again like 2 days later! gotta get this figured out as I got a rejection for my inspection sticker! ugghhhh!!
I had the tighten fuel cap come on, then the SES light came on. I replaced the fuel cap at auto zone. I unplugged the battery to reset the SES light. It went off. Then driving to work today I got the tighted fuel cap!
2005 Chevrolet Trailblazer 50,000 mi,
I have put 3 caps on and it stops for a month or two then does it again.
2005 Chevrolet Trailblazer 73,000 mi,
Yeah, I bought my car from the Chevy dealership used. Two weeks after I had bought it, my check engine light came on! So I brought it back to the dealership, and they told me it was the gas cap and it needed to be replaced. It costed me about $100. TWO WEEKS AFTER I BOUGHT IT. Poor customer service, in my opinion.
My check engine light came on and then I was told that if you have low gas or the cap isnt on tight then the light will come on.. I had low gas so once I filled it up the light went out.. Nice thing to know..
About a week ago the gas cap light came on. So I pulled over and tighten the cap, and It went out. So today the check engine light came on and I push the onstar button for them to do a diagnostic test on my truck. After they did the test he said to check the gas cap, and it should go out.It didnt he said if it dont go out in 7 days go to dealer. So tomorrow I will go and get a gas cap and fill my tank up. Wish me luck Trailblazer owners
Gas cap failed suddenly. Replaced at Autozone and SES light reset within 400 miles
2008 Chevrolet Trailblazer 70,000 mi,
Now at 101,000 miles i gave up on gas caps and replacing vent lines
2003 Chevrolet Trailblazer 55,000 mi,
Check Engine Light Due to Gas Cap Issue
This happens whenever I change gas stations, so I only fill up at BJ's and the light goes out-lol.
2005 Chevrolet Trailblazer 198,704 mi,
Tighten fuel cap comes on the a day or two later check engine light comes on i have replaced gas cap and problem still happens. Mechanic hooks it up and it says there is a gas leak and then he resets it then light comes back on a week later. I think its time for Chevy to have a recall and fix the issue
My car routinely fails the emission test due to a bad gas cap. I replace the cap with a non dealer part, the check engine light goes out and the car passes emissions. A couple weeks later, the problem starts up again.
2007 Chevrolet Trailblazer 50,000 mi,
Replaced cap with one bought from the Chevrolet place. Light continued to come on at intervals. Had car repaired and light still comes on at intervals.
2007 Chevrolet Trailblazer 149,000 mi,
On and off
2005 Chevrolet Trailblazer 85,000 mi,
i bought new gas caps 4 to be exact, I went to the dealer and bought a factory one and so far its been ok
I have had this happen a few times. gas cap becomes loose while driving.
2007 Chevrolet Trailblazer 110,000 mi,
I have had this problem three times now. The first time I was told I needed to replace the fuel cap, I did this with no positive result. I then took it into another store and they told me it had to do with a part in the fuel emission system. Dirt gets underneath it and causes issues. I have had to replace it twice, and now I am on my way into the auto shop in the morning as my check engine light is one once again. It seems to happen every 1 - 1 1/2 years. I was also told that this is a fault of the Chevy Trailblazer.