hello. I have a 2001 LR D2. 130k. This was a junker and Ive been working on her a lot. Two issues are making me crazy. One misfires on 1,3,5,7 only. Ive honestly tried everything I can think of. The newest is in drive, she will go in and out of overdrive. When you get to the spot where you dont need any pedal but the engine isnt breaking either it bangs back and forth like the Ujoints or Tcase are falling out! Give it a touch of gas and shes fine? Tranny fluid is full and clean and looks great. Ive never tinkered with the tranny so I would like some sage advice!

 

Rotoflex maybe - it is a big rubber donut on the rear driveshaft. Also standard or Auto transmission - there is no overdrive on my auto

 

One misfires on 1,3,5,7 only.
Bad Injectors, wiring/connectors, leaking intake manifold, leaking injector o-rings, bad plugs, bad wires, exhaust leak, O2 sensor upstream. Compression check yet?

.....in drive, she will go in and out of overdrive. When you get to the spot where you dont need any pedal but the engine isnt breaking either it bangs back and forth like the Ujoints or Tcase are falling out! Give it a touch of gas and shes fine?
Oddly, I was surprised to learn the MAF affects shifting into OD. Mine would only shift into OD if I hit 50mph and quickly let off the gas. That may be part of the problem, fixing the first part may solve this.

 

I have replaced MAF sensor, injectors, plugs, wires, vibration sensor, coil packs, intake gasket, throttle body position sensor, crank and cam shaft sensors and all four O2 sensors, fuel pump module. I'm using Disco Bobs 3 Amigos reprogram OBD2 chip update. I swapped the ECU out of my 03 and nothing changed. I replaced the injector wiring harness and redid all the rail grounds. Compression is good all the way around. I too think both problems are related but danged if I know where to go from here

 

I hope you saved all those parts because that's what the previous owner did before he gave up and sold it to you. It's time for a suitcase of beer, a multi-meter, and a can of electrical contact cleaner. Every Single Connection needs to be inspected to be sure the pins and sockets are in place and not corroded. That the wires are not chewed, pinched, or have bare spots. That all fuses and their sockets are good. That something isn't unplugged. I would start at the O2 sensors since it is a left bank problem and work forward with the wiring. That it's isolated to one side of the engine is great, it is the random misfires from both sides that drive me nuts. I wonder if it could be a bad cat, I have not experienced this either. The only time I had a lean bank code it was due to driving with less than 1/4 tank most of the time, the fuel pump is tired and gets hot without at least 1/2 tank. Always keep the tank at 1/3 or better.

 

In my (limited) experience, misfires on all the cylinders on one bank are caused by a problem with the upstream O2 sensor or its wiring. That was the case with my truck and with at least a few others I've seen reported It's the only thing shared by all four cylinders on one side.

If you've replaced the Bank 1 upstream O2 sensor it may be its wiring harness, although O2 sensors bad out of the box are known on this forum. You could try swapping the upstream O2s side-to-side. Like Lisa said, inspect the connector carefully. You could also test continuity on each of the four wires from the Bank 1 Position 1 sensor to the ECU. Good luck.

 

My fix was a new fuel purge valve Hyundai one
when it wouid purge it sticks open dumping air fuel into your intake really messing things up