I have an evap leak (small) code that pops up every few months.

Looking for guidance on how to best troubleshoot. I see there is a test port? Can that be used to any advantage?

 

Smoke checking is a good way to find the leak, but have you looked at the evap hoses or replaced the gas cap yet?

 

From everything I have read the most common reasons are like Busted back has mentioned are the hoses and the gas cap. The 2 times I have had this problem on my other XJ's it was always the gas cap.

 

unless you have a smoke tester that port is pretty much useless. gas cap is the first place to start check for cracks around the gasket otherwise the hoses near the canister and test port tend to crack and leak... inspect those and report back

 

Thanks for the replies. Hoses look good (based opn visual inspection, though I need to do a better interrogation back at the canister area).

Cap order is on the way. Hopefully that will do it.

Is there a leak down test that I could do to know if I have fixed it or is it typically a see what happens type of thing?

 

If it is a small leak and you are unable to find it there is a product that can be added to the system to stop small leaks. I have used it in the past and it did work in several cases for me and stopped them.

As in all things YMMV.

 

I had same code few weeks ago. I found that I had dry rot on hoses that lead into the intake port and a crack in the hose that leads from the canister back to the tank underneath. Once I replaced those code went away.

 

could you post some pics of the hoses you had to replace?
do you have the EVAP can under cargo area of your XJ?

 

I'll post some tomorrow, it's dark right now. I'll be under it in the afternoon anyway. There's the charcoal canister under the cargo area and the evap part in the engine bay. I spent all of 30 minutes tracing the hoses/connections. Once I replaced them, no more issues.