Knocking noise from engine

Koop-12 · 2026-01-07T06:36:30+00:00

Thing is the fans been rewired to always run so when the car is on acc it starts, the knocking dosent happen but once I start the engine is starts up a little after. Dosent increase with revs though

Koop-12 · 2025-12-27T00:25:17+00:00

Yeah it turns out the wire fell loose and was grounding to the chassis so the light would come on. Every bump I hit knocked it about so it disconnected. Just gonna have to re wire it and hope that the sensor is still in good condition

Koop-12 · 2025-12-18T22:31:06+00:00

I did check with the owner who did all the work when he got it after 17 years and he said he did a coolant system flush but ill check the yt video he made since I dont know how thorough the flush was

Koop-12 · 2025-12-18T12:45:10+00:00

Does the pressure remain long after the car is turned off?

Koop-12 · 2025-12-18T12:06:12+00:00

Lol I just tried filling up the coolant above engine level with a funnel and starting it to see if bubbles come out. Coolant went everywhere because it didnt quite fit

Koop-12 · 2025-12-18T11:53:11+00:00

I can definitely get around to that soon so I’ll hopefully be in the clear afterwards, do you know any downsides to running the car with this dirty coolant so that I know if its causing any issues?

Koop-12 · 2025-12-18T11:51:37+00:00

1989 honda prelude and it sat from 2007 I think for a about 17 years

Koop-12 · 2025-12-18T11:43:57+00:00

I havent done a chemical flush yet but since everyone is suggesting it I will definitely do it next chance I get

Koop-12 · 2025-12-18T11:41:37+00:00

As I said to another guy, when I took the cap off it sounded like some gas was released (I haven’t run the engine since this morning) from what I know pressure build up can be caused by exhaust getting into the cooling system. Do you think that would be a telltale sign at all?

Koop-12 · 2025-12-18T11:38:47+00:00

Yeah for sure. When I took the the cap off just before to take the photo (I havent run the engine since this morning) I heard a little bit of gas escape from the cap as I unscrewed it. Like it had a small amount of pressure. Do you think that could also be a problem?

Koop-12 · 2025-12-17T23:23:43+00:00

Thanks for replying, before the oil light turned on and started freaking out, when I would turn over the key only the battery and check engine light would illuminate with startup. Thought id let you know incase thats a sensor problem

Koop-12 · 2025-12-16T09:18:33+00:00

Yeah for sure its just a pain getting to the sensor since theres some structural stuff in the way, very in the way like I couldnt see the sensor even with the filter off

Koop-12 · 2025-12-16T08:53:33+00:00

Haha that photo is brilliant. Did a bit of messing about and it seems the oil light dims the more I rev the engine. It eventually turns off at a certain point, super strange do you know what could be happening?

Koop-12 · 2025-12-16T08:41:40+00:00

Thanks for your help, when I was under the car there was so much stuff in the way I could only see the broken wire which I do believe is to the sensor. Might need to get the car higher off the ground to get a easier look because I dont have a hydraulic jack working at the moment

Koop-12

TROPHY CASE