Hi folks,

this forum has been super helpful and super knowledgeable and a big thank you for all the help so far. I started out, with no mechanical or auto experience, and was able to recently update my timing chain, cooling system, oil pump, etc. thank you again!

when I got this disco2, it had O2 codes P0134, p0154 so I changed the sensors with new ones. There were a couple of exhaust leaks and I fixed them to the most part but still some leak from exhaust manifold gasket ( where it connects to the downpipe) which I plan to fix soon.

Now, I’m still getting these codes and wanted to get help and ensure Im on the right path:

p0154 bank 2 sensor 1 ( front passenger)
p0134 bank 1 sensor 1 (front driver side)
p0135 bank 1 sensor 2 (rear driver side)
p0174 system too lean bank 2
p0171 system too lean bank 1

Known problems:
the car has aftermarket cats (orig was stolen)
air intake after the air filter has missing clips near the maf sensor so I temporarily ducktaped it ( clips ordered and expecting next week)


other thatn that the engine sounds ok, runs ok but loud because of the leaks

I’m planning to clean the maf sensor and fix the exhaust leaks. Anything else I should be doing?


( i recently did these updates:Oil change, air filter and oild filter and at 156k new Timing chain
New Oil pump and gasket
New Water pump and gasket
Oil pan gasket
Fixed stripped threads
New coolant hoses
New coolant expansion tank
New 185f thermostat with inline mod
New radiator
New O2 sensors front
New. belt
New front crank pulley main seal)


thanks in advance!

 

Wanted to mention that before the inline thermostat mod the engine temp was >200f occasionally reaching 220f. I only drove about 20-30miles like this and updated the cooling system with the inline mod and now it runs at 175-188f.

 

sounds like you are on the right path.

be sure to clean the MAF when it is completely cold. if you clean it when it is hot you can break the filament that measures the air flow.

 

P0171 and P0174 indicate a vacuum leak or leaks affecting both sides. I'd start with a smoke test of the intake system.

You can do it with a cigar and a length of rubber tubing. Just search YouTube for "intake smoke test cigar".

 

Sounds like you have gotten bad sensors out of the box, I went through about six the last time I bough sensors before i got a good one. Here is how to test. Monitor the sensor voltage on cold start. The sensors should go close to 1 v, if they don't, they are bad. If they do go to close to 1v and then trend down close to zero, you have a vacuum leak or plugged injectors (very rare).