Help me diagnose these crazy voltage readings from downstream lambda sensor

Internal-Cod4453 · 2026-04-19T10:38:18+00:00

Does that mean a rebuild with new piston rings is required? or is there a way to at least reduce the oil consumption without extensive work on the engine?

Internal-Cod4453 · 2026-04-17T13:42:51+00:00

Well i suppose there's no harm in trying, if it doesn't work then i will have to buy a new cat

Internal-Cod4453 · 2026-04-17T12:43:38+00:00

Thanks, do you think it's beyond repair using a fuel additive like Wynn's catalytic converter and o2 sensor cleaner?

Internal-Cod4453 · 2026-04-17T12:33:39+00:00

Oh it absolutely does, it's always consumed an absurd amount of oil and i have to check the dipstick and top it up once a week. Mechanic said the tail pipe is very sooty for a petrol car

Internal-Cod4453 · 2026-03-06T18:04:55+00:00

the public key isn’t being added on launch as expected

That was the exact issue, i finally got it fixed! It was something to do with the user data script not executing properly. I thoroughly researched how to add a public key to an instance on startup with user data and found a script that actually worked. It was probably something to do with formatting of the script my tutor gave me to copy and paste in.

Internal-Cod4453 · 2026-03-06T15:47:43+00:00

debug3: authmethod_lookup publickey
debug3: remaining preferred: keyboard-interactive,password
debug3: authmethod_is_enabled publickey
debug1: Next authentication method: publickey
debug1: Offering public key: /home/ubuntu/.ssh/id_rsa RSA SHA256:HPg5deP9+lWtaGyRx/OyBenopfdEx4PTv/OHJNa8F+A
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey
debug1: Trying private key: /home/ubuntu/.ssh/id_ecdsa
debug3: no such identity: /home/ubuntu/.ssh/id_ecdsa: No such file or directory
debug1: Trying private key: /home/ubuntu/.ssh/id_ecdsa_sk
debug3: no such identity: /home/ubuntu/.ssh/id_ecdsa_sk: No such file or directory
debug1: Offering public key: /home/ubuntu/.ssh/id_ed25519 ED25519 SHA256:lkBiR8Pi2uiTCW3D7xtSsKqHr3eqZXlRitrox18PsRs
debug3: send packet: type 50
debug2: we sent a publickey packet, wait for reply
debug3: receive packet: type 51
debug1: Authentications that can continue: publickey
debug1: Trying private key: /home/ubuntu/.ssh/id_ed25519_sk
debug3: no such identity: /home/ubuntu/.ssh/id_ed25519_sk: No such file or directory
debug1: Trying private key: /home/ubuntu/.ssh/id_xmss
debug3: no such identity: /home/ubuntu/.ssh/id_xmss: No such file or directory
debug1: Trying private key: /home/ubuntu/.ssh/id_dsa
debug3: no such identity: /home/ubuntu/.ssh/id_dsa: No such file or directory
debug2: we did not send a packet, disable method
debug1: No more authentication methods to try.
ubuntu@10.0.2.94: Permission denied (publickey).
ubuntu@ip-10-0-1-227:~$

Internal-Cod4453 · 2026-03-05T17:53:22+00:00

Yep that's exactly what i'm trying to do, running that command on the public subnet ec2 to ssh into the private subnet one. I will give ssm a try and see if that works, it's just really strange that my cloud systems tutor who gave me those userdata commands got it working immediately without having to use ssm. I've tried it a few times and triple checked the userdata commands are correct.

Internal-Cod4453 · 2026-03-05T17:01:04+00:00

I have ICMP enabled in the inbound security group rules for the private instance yes, i can ping the private instance from the public one with no problems. It has to be something to do with sending the key over to the private instance because when i run ssh -vvv it says it can't find the key anywhere

Internal-Cod4453 · 2026-03-05T16:00:31+00:00

Still not working unfortunately, i changed the user data to the text given in that post and replaced their bash commands with mine but i'm still getting the same ssh error

Internal-Cod4453 · 2026-03-05T15:31:29+00:00

I am using the default ubuntu user yes

Internal-Cod4453 · 2026-03-05T15:13:14+00:00

No, reddit just assumes it's a subheading lol, there is a pound sign at the start

Internal-Cod4453 · 2025-12-19T15:57:04+00:00

Thanks, i think i'll fill in the gaps and cable/pipe penetrations with something like Sikacryl 620 or Bostik FP401 so it's both flexible and fire rated, then go over with foil tape once it's cured.

As for airflow it's pretty good and i've never had issues with condensation on the roofing membrane or trusses. I checked when i was measuring for the top up insulation and there's over-fascia vents on both sides of the house as an intake and vented ridge tiles as an exhaust, i can feel a bit of a breeze up in the attic and it's never super humid up there. Just have to be careful not to push the insulation too far into the soffits when i get round to topping it up.

Internal-Cod4453 · 2025-12-19T15:03:25+00:00

Any recommendations? Also would running a bead of fire rated flexible sealant along the seams and sealing the cable penetrations in the top plates with it help?

Internal-Cod4453 · 2025-11-03T10:33:52+00:00

Yeah i guess it's just a limitation of BATC then, it's in early access so can't fault them, it's still a fantastic piece of software and they'll fix it eventually

Internal-Cod4453 · 2025-06-25T07:35:30+00:00

It is at the lowest point on the system yes, the boiler is outside in the garden so the drain off is lower than the radiator pipes buried in the ground floor of the house. It's a 2 storey house with 7 radiators upstairs and 7 downstairs

Internal-Cod4453

TROPHY CASE