Rubicon Owners Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
71 Posts
Discussion Starter #1
My check engine light just came on. '03 Rubi, 4.0 w/72K. Any likley issues to check first before I have a scan done?

Thanks,

Ken
 

·
Registered
Joined
·
962 Posts
My check engine light just came on. '03 Rubi, 4.0 w/72K. Any likley issues to check first before I have a scan done?

Thanks,

Ken
You might have your codes right on your speedo cluster. I think you turn your key to the right to turn on the electrics but not all the way to start. Do that 3 times in quick succession and you will see your code or codes light up on the speedo cluster area.

Fellows here on ROF should have that process down and can correct the instructions if needed. At least it works on my 05 rubi.

If that doesn't work your local parts store has a selection of code readers. Pay extra to get a better code reader too.

Also many of the parts stores will come out and plug in their code readers and give you the codes for free.

Keep us informed and let us know what you found.
Bob
 

·
Administrator
Joined
·
10,850 Posts
Auto parts stores will read the code for free but they won't clear the code. I have a ScanGauge II that sits on my dash so I can keep an eye on coolant temperature, battery voltage, etc. It will also read and clear codes - very handy.
 

·
Moderator
Joined
·
1,533 Posts
I’ve had that code three times over the years and it was a loose gas cap every time. One of the three, I had to replace the cap and I did so buying it from the dealer. My research on here said the dealer replacement had more reliability.
 

·
Registered
Joined
·
71 Posts
Discussion Starter #9
Light returned even after new gas cap, any likely suspects I should check for evaporative leak error code? Thanks
 

·
Administrator
Joined
·
10,850 Posts
All of that evap plumbing is hidden between the plastic wheel liner and the tub at the rear on driver and passenger sides. I pulled the liners out when I was outboarding my shocks and never put them back - makes it easy to access those areas. I would check all of the hoses. It's probably going to be a PITA to check with the wheel well liners in place.
 

·
Moderator
Joined
·
3,472 Posts
Light returned even after new gas cap, any likely suspects I should check for evaporative leak error code? Thanks
Last time my TJ had this code I found a very loose line under the hood, drivers side, next to the intake manifold. Re-setting that connection and adding a clamp fixed it for me.
 

·
Moderator
Joined
·
3,472 Posts

·
Registered
Joined
·
962 Posts
Mouse, did you find by eye or did you need to use smoke machine?
Ken,
I made a paint can smoke machine from a utube example. I was chasing down a check engine light and gave it a try.

I hooked the smoke tube up to the intake after removing a vacuum line that goes to the brake system. I used a 12v air compressor for airing up tires. I did find a small leak and replaced a hose. It didn't change my check engine light problem though.
Bob
 

·
Registered
Joined
·
36 Posts
I wouldn’t abandon the gas cap as the culprit unless you purchased the new one from the dealer. I’ve had good luck taking the gasket off the parts store gas cap and putting it on the factory unit.
 

·
Premium Member
Joined
·
2,456 Posts
I've chased that same error code for years, on and off about every year or year and a half. I've found rotten evap hoses and replaced most hoses now, over the years. I'll typically get the code, check and find a rotting rubber hose somewhere or a couple of times it's been a loose gas cap. I make sure and twist the clicking gas cap 5-6 times to make sure it seals. Funny thing is I got the code today... Coincidence??? hahaha I'll be checking the hoses/gas cap tomorrow, ...again!
 
  • Like
Reactions: johncanfield

·
Moderator
Joined
·
3,472 Posts
I took the camera with me to the garage, and looked through the hoses and didn't see where that repair was made many years ago. Then, the camera battery was dead as well...I'll have to try again later when I have power for the camera.
 
1 - 19 of 19 Posts
Top