So to check this thing, you just put the keys in the ignition, turn, and check the display? Will it show nothing if no code is sent?

My truck is still running a little goofy and I just want to figure it out before the winter!

 

"service engine light" is a reminder light. Nothing more.
"check engine light" means the computer is signaling a problem of some sort.

very different.

 

Service engine is resettable by getting under glovebox, Check engine needs reader. Which is it?

 

I'm talking about the thing underneath the passenger seat. I don't have a check engine light on.

 

mbwoodyard... what year is your truck? I'm guessing pre-1996. Good idea to put it in your signature so we have a better fix on your situation.

 

its a 1995. 5sp.

 

With the 1995 you have the last of the 14CUX fuel injection systems and consider yourself fortunate. While it's not the most sophisticated system it is reliable and easy to fix. Under the passenger seat you have an OBD1 diagnostic code reader. The numbers are displayed in red LED. Go here for quick explanations of the codes.

Land Rover Troubleshooting: retrieving fault codes

Also, download the RAVE for a complete service manual for your truck.

land rover service factory manual RAVE download land rover resource, service manual, workshop factory manual, download, rave, vehicles including discovery, series, defender, range rover, freelander, LR3, Handbooks, Catalog, Catalogue, Land Rover Inte

 

Awesome thanks! So if there is nothing displayed, than it is not throwing a code? My truck is just running way too rich for some kind of code not to be flying around somewhere.

completely off subject, but i asked my dad if he had any ideas and he mentioned a cold start valve? Anyone know if and where that existed on my car?

 

Like Paul said, it's not the most sophisticated. It could run like crap and potentially not display a code, so long as the sensors are giving information that is in range, even if the information is completely bogus ...easy to keep them running, but many times you'll have to bust out the meter and actually check things, instead of relying on the OBD.