So I thought I found my leaks but let me back up first. CEL is evaporative emission leak (small leak) and my gascap light is coming on all the time now. Gas cap is tight. I figured I'd ask here first before I take it for a smoke test Monday. Any suggestions?

 

Any ideas?

 

Take a peek at the Evap System Map in the FAQ section and trace the lines. You'll likely find a split line end or a broken hose clamp - might save you from paying for the test...

 

It's been a while since Iv been on here but update: I took my truck to a local muffler shop that did a smoke test on it, idk if they did it right but they didn't find a leak. I was standing there watching and didn't see anything but also didn't look like they knew exactly what they were doing. Every so often the CEL will go off for about 100 miles then it comes back on. Any ideas?

 

Smoke test on the exhaust unfortunately has nothing to do with the evap can or fuel cap seal.

Go back and see Post #3

 

I believe they did it through the Evap system. They hooked it up to some vacuume line under the hood which I believe to be correct but I maybe wrong. Ill double check.

 

Is the gas cap original? If so replace it with factory cap. The o-ring gets flat over time. What year, Engine?

 

Already replaced with 2 caps.

 

OE caps or walmart? I have seen where cheaper caps will cause check engine light. Usually the cap doesn't fit quit right. Or the pressure rating is off.

 

O Reilly caps but when I pump get and take cap off I can hear it release pressure so I thought it was ok.