Hey Guys,

I am new on forum and also new with Land Rovers. My 2001 Disco II has a poor engine performance, with check engine light on and sometimes even blinking.

I checked on OBD Code reader and it showed up several codes:

P0154, P0155, P0135, P0453, P0327.

Before it showed up also misfires and I changed all spark plugs with Bosch Platinum +4 plugs. I tried to reset check engine, but after several miles it showed up again.

Now i am going to change O2 sensors and maybe you can recommend what can be other cause? And can O2 sensors affect fuel consumption and also engine performance (while accelerating its losing power and shaking)?

Thank you for help and any comments are welcome.

 

How many miles on the Disco? You should add your details to your signature line.

Take a look at the STICKY's a the top of the Disco II forum.

https://landroverforums.com/forum/di...service-29020/

Look at doing the major service items......especially the induction cleaning.

And yes malfunctioning O2 sensors will/can cause your MPG to plummet.

Mine went from 14-15 MPG to 8-9.......

Use the search function for oxygen sensors......there are no shortage of issues.

 

If you did not also change the plug wires you only fixed half the problem.
You need to use either STI, Magnecor or Kingsbourne plug wires.
After that is done reset the check engine light and drive it and see if the codes come back.

 

Thank you for your comments. Mileage is 85K. After changing spark plugs I drove around 100 miles and will I have to replace spark plugs again, or only wires will be enough? Now I stopped driving until wires will be replaced. Will update about the situation.

 

The new plugs will still be fine. Just the wires at this point.

 

So, after 14 error codes with misfires, O2 Sensors and Knock Sensor, I changed spark plugs with Bosch Platinum +4, plug wires with Kingsborne 8mm and all 4 oxygen sensors with Bosch Premium O2 Sensors, also changed air filter, cleaned the place where MAF Sensor is connected, but its still throwing all of the same error codes. I cleaned them twice but it didnt help.

Still its showing misfires on cylinders #2, 4, 6, 8 and all Oxygen sensors, plus random misfire and knock sensor.

Does it take some time to new parts to be adjusted, or it still might have some leak and there still might be misfires? SES light is still, but its starts blinking sometimes. Any ideas what can be wrong? I already have no idea what to change or what to do with the car.

 

If it were me, I'd replace the crank sensor as that controls spark.

 

Clear the codes today and get back to us with them one more time.
Per the posted codes, you did have 2 bad 02 which it sounds like you replaced, but so far everyone has forgotten to mention the 327, failed bank 1 knock sensor which could cause you many issues other then the 453, evap control system pressure sensor high input.
So deal with the knock sensor first.

 

I erased all codes, but after 1 mile of driving SES light came on and started flashing and it threw up all of the codes - misfires on 2,4,6,8 cylinders, random misfire, front O2 sensors, knock sensor, 1300, and 0453. Do i have to change both of the knock sensors, or only the first one? And how difficult is it for non-professional mechanic to replace it?

 

I took the car back to mechanic and as he said it might bad MAF sensor and it causes misfires and O2 codes and also detonation from these misfires cause Knock Sensor. He was suggesting to replace MAF Sensor and fuel filter. Can it work this way? can MAF sensor cause the same misfire and O2 codes after installing new plugs, plug wires and all 4 O2 sensors?

Please help guys, cuz this car is already making me crazy