Hi All,
I’m still having trouble with the 4th gear incorrect ratio and engine too lean codes. I tried replaced the transmission speed sensor and no go. It DID stop the hard shifting though. For the lean codes I’ve checked the air box for proper seal, checked for vacuum leaks, replaced the MAF and BOTH oxygen sensors, no go on that either. The car runs fine though.
any ideas?
Also we’re thinking about moving back to California and I with this damn “service engine light on I wouldn’t be able to register the truck. Any help is greatly appreciated.

 

Which lean codes? 02's working? Usually lean codes with working o2's are related to vacuum leaks, injector o-rings, hose fittings, loose intake manifold bolts, and bad power brake booster are frequent sources. Unplug the maf and see if your 4th gear code goes away.

 

Check your fuel trims then get to smokin'


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What am I checking with the fuel trims and with what? I’m NOT a mechanic nor do I have a sophisticated analyzer. I just have a fixed dongle. No one here in this small city works on these trucks. Thanks
p.s. I just ran a scan and instead of the lean codes it changed to P0171 & P0174 fuel mixture imbalance WTF?

 

A lot of us get this Ultragauge.
https://ultra-gauge.com/ZC/index.php...roducts_id=195
They are only $84 and you just plug it into your OBD2 plug.

 

A couple points:

1. As you are new hear, a couple tips. Most of us do not memorize the meanings of the trouble codes aside from the 030X codes. You will get more help if you look up the meaning of the trouble code in the Rave manual and post the meaning along with the code numbers. If you don't have a copy of the Rave manual suggest you do a search and download it.
2. The ultragauge is excellent for monitoring temperatures and quickly monitoring codes, but not ideal for troubleshooting. When troubleshooting fuel mixture codes it is absolutely essential to be able to view an analog plot of the oxygen sensor voltages and one of the cheapest and most effective tools for that is a bluetooth Elm327 obd2 tool coupled with the free torque app for android. There are some iphone apps that will also plot analog voltage outputs but I hate my iphone so rarely use it, I will leave it to others to suggest and app or a search.
3. The first step in troubleshooting codes on a D2 is to make sure the oxygen sensors are working properly, that is the point of #2. Often bad oxygen sensors are the cause of codes.
4. Lean codes and imbalance codes are almost always a result of a vacuum leak (see my post above). We need to know what if anything was recently done to the truck in terms of repair or maintenance work, as that work might have caused the vacuum leak. People frequently use a smoke test to find vacuum leaks, there are numerous videos on making your own smoke test machine and smoke testing the intake tract of engines which is what @Roont is referring to. This also the point of looking up the fuel trims, as if they are high it indicates you are actually lean.
5. You state you are not a mechanic, but here you are owning a LR and asking for a help on the forum. You have three choices
   1. Take it to a mechanic - negatives and positives are well known.
   2. Learn to troubleshoot and repair with the help of the forum - the D2 is one of the best learning platforms ever made. Provides frequent opportunities to learn, comes with an amazingly large and helpful community and knowledge base, and is simple to work on with common hand tools.
   3. Get mad and sell it - frequently done. I have bought 24 due to #3
6. Not for nothing, but with the minimal facts you have provide I am betting bad 02s are part of your problem and a vacuum leak is part of it.