Hello all, I am new to Jeep TJ's and hope there is someone out there that can help me with an issue I am having with my recently acquired 2006 Rubicon TJ.
To start off I will let you all know that I am a very experienced mechanic but have been working on Hot rods and 50's/60's Chevy's for the last 18 years... I have a lot of electrical experience so you can talk technical with me... but it's been a while since I have done much on modern cars and why I hoping to find a little help here.
Shortly after I purchased this Jeep I got a check engine light. I had taken the Jeep in for an emission test the week before and it passed with flying colors (including testing the gas cap). I checked with a scanner and got a code PO440. I did what you should always do and checked the gas capo to be sure it was installed correctly and tight (it was). I reset the code and after about 3 or 4 days the code reset itself. I replaced the gas cap and after about 3 or 4 days the code reset itself.
I checked all the visible vacuum lines and vapor hoses and see nothing obvious. The fuel tank was below 1/4 so I filled the tank and drove it for over a week on short little trips so that I could get a lot of engine starts and stops. For over 100 miles no check engine light. While on the highway with about 2/3 full tank the check engine light came on... I checked and it was a Code PO440 again. I reset the code and after 4, 5 or 6 starts the light was back on. I filled the tank again and reset the codes... no light. I filled the tank several times not allowing it to drop below 3/4 full... no light. Now that I have let the tank get just below 3/4 full the light has come back on.
Does anyone know or have an idea where I am loosing vacuum in the EVAP system or why it only seems to set a code when the tank gets below 3/4 full?
Thanks,
Rick
To start off I will let you all know that I am a very experienced mechanic but have been working on Hot rods and 50's/60's Chevy's for the last 18 years... I have a lot of electrical experience so you can talk technical with me... but it's been a while since I have done much on modern cars and why I hoping to find a little help here.
Shortly after I purchased this Jeep I got a check engine light. I had taken the Jeep in for an emission test the week before and it passed with flying colors (including testing the gas cap). I checked with a scanner and got a code PO440. I did what you should always do and checked the gas capo to be sure it was installed correctly and tight (it was). I reset the code and after about 3 or 4 days the code reset itself. I replaced the gas cap and after about 3 or 4 days the code reset itself.
I checked all the visible vacuum lines and vapor hoses and see nothing obvious. The fuel tank was below 1/4 so I filled the tank and drove it for over a week on short little trips so that I could get a lot of engine starts and stops. For over 100 miles no check engine light. While on the highway with about 2/3 full tank the check engine light came on... I checked and it was a Code PO440 again. I reset the code and after 4, 5 or 6 starts the light was back on. I filled the tank again and reset the codes... no light. I filled the tank several times not allowing it to drop below 3/4 full... no light. Now that I have let the tank get just below 3/4 full the light has come back on.
Does anyone know or have an idea where I am loosing vacuum in the EVAP system or why it only seems to set a code when the tank gets below 3/4 full?
Thanks,
Rick