2nd post!

I bought my D2 with a blown motor sitting for 5+ years. After putting it together I installed brand new Bosch orange plug o2s like I've seen suggested on here.

Here's the thing. I still get p0133 and p0153. Always bank 2 sensor 1 first, then 300 or so miles later bank 2. I also get catalytic converter codes P0420+P0430 with these even with brand new branded cats. The originals were hacked off while the truck sat in a field.

I've replaced both o2s Again, with the same Bosch sensors. I've replaced the pigtail ends on both sides, and my ECU was replaced for a separate issue. I smoke tested the truck and found a small leak at the PCV valve where I forgot a hose clamp. It has new NGK Iridium plugs, 7mm wires, and new coil packs. I just replaced the MAF for the heck of it. On live data they both switch 3 times per second.

Truck runs well aside from a slight stumble at idle, no idea why it has that but it isn't noticeable. Heard it is just an overlapping cam from factory. Fuel economy is crap but I drive like crap too, no other codes but a P0462 for a equally as frustrating gas gauge.

Any help is greatly appreciated, I've put so much TLC into this car and this is the last of the issues. At this point I'm ready to sell because my Suburban does everything the Disco does, but slightly better.

 

I had a similar issue this year when I replaced all of my O2 sensors. I think that I've solved my problem by using the premium/OE Walker O2 sensors. Looks like AB uses the economy Walker sensors in their kit and that was causing me similar issues to what you reported. Rockauto has both types and the OE are only a few dollars more. People seem to have issues with the Bosch sensors which is puzzling as I always try to use Bosch parts whenever I can.

 

Guys don't forget whenever you give your D2 a tune up or replace an MAF, O2 sensor, or clean the IAC you should reset the adaptions. The ECU has a baseline and then it will "adapt" to whatever the sensors are telling it over time. It's a good idea to reset your adaptions and then drive it and the ECU will learn from the new sensors. If you don't do that it's technically just using the old adaption settings with the new sensors and it'll take a while for it to re-adapt after several drive cycles. Just removing power from the battery will not reset the adaptive settings. It was always performed whenever a LR was in the shop for a service with a T4.

 

I think I asked you this before, but how do you do this with a Nanocom? I think I’ve seen it in there, but can’t remember exactly.

Also, how should I go about cleaning the IAC valve? You probably saw, I’m chasing a misfire that is probably based on a vacuum leak and after I do the smoke test today, it probably would be a good idea to clean it up.

EDIT: Check the question on resetting the adaptations. I was able to easily find it and get that done. Still wondering about cleaning the IAC valve.

 

I cleaned my IACV with carb cleaner. They do get really dirty and full of gunk. Just take it out and use the straw to get in there. you can move the valve manually to get the stuff you can't normally see. I did at one point a long time ago, dipped the IACV in parts cleaner/degreaser. Just the end with the openings FWIW.

 

Thanks! This will be on the short list when I’ve got a few minutes here and there- worked on the property all day today…

 

An update to this saga. My voltage running was around 12.5 volts, after cleaning grounds and replacing the voltage regulator in the Denso alternator, it was at 14 flat and the codes never came back.

 

That’s good news. Thanks for letting us know.

 

im currently going to this now. All you did was clean the ground and replace the voltage regulator online your alternator? Where did you buy it from because I can’t seem to find it. I replaced my o2 with a Bosch sensor and the p0133 is there. I’m going crazy trying to fix this

 

When checking for alternator behavior, run the engine up off idle - at least 1500rpm. All measurements should be in the 13v - 14.5v range (ish). Measure from the output post on the alternator to the case of the alternator; move the black lead to the engine block; move the black lead to the neg battery post. If those are all the same and low, then it is your alternator (probably the voltage regulator inside the unit). If those vary from ground to ground, then you have a situation where you have a bad connection. Could be a bad connection, could be a bad cable, could be any other part in the electrical path. Moving the black lead to more of those points in between the alternator case and the battery post will narrow it down to the actual point of failure.

If you haven't done all of this yet, then don't buy any replacement parts yet.