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02 Honda civic loud knocking and belt whine issue :(

Okay so let me start off my saying I purchased this car salvaged 5 yrs ago and have been doing extensive repairs on the car, new engine, suspension the works. But started having this knocking sound near my timing belt/water pump. I went into a shop and they said it was the ac compressor and it was going to cost 800 to fix, I said no because it seemed to high for a job like that and I called up my mechanic from back home (NY, I’m working down in NC). He said if the sound gets louder cut the ac/power steering belt since I don’t really need it because winters coming up. I cut the belt, the sound is still there. The sound is really loud when I first start it but dies down when the engine is warm and unnoticeable on the highway. Just a side note, the ac belt has been squealing if the ac is turned on/if it’s raining out also I am do for a timing belt/water pump change. I have done regular maintenance on this car, every 3500 miles with synthetic oil (spoiling the engine). I really hope I can drive it back up to NY to get it fixed by my mechanic. Any advice would be greatly appreciated!

First of all, I wouldn’t trust your NY mechanic with a repair like this - he clearly doesn’t understand how automobiles work. Cutting your A/C serpentine belt will not only disable your power steering (a bad idea in itself), but will cause your defrost not to work, because it uses the A/C system to draw moisture out of the interior. And “cutting” the belt? I’m wary of anyone who would suggest that you actually destroy a part of your car in pursuit of the noise, rather than correctly removing and replacing it.

It sounds like maybe your water pump pulley bearing is going bad - I think it’s probably unrelated to the A/C belt squeal. The only way to isolate the noise is to remove each seprentine belt until the noise stops, and if it doesn’t stop, then it’s probably something with your timing belt tensioner or pulley.

Thank you for your comment! I actually trust my mechanic wholeheartedly, he’s pointed out issues with my car that every other shop have not. I had a huge hole in my strut tower ever since I bought the car, I’ve been in literally hundreds of shops and none of them have ever mentioned that to me until my current mechanic. Cutting the ac/power steering belt might have not been the best choice but he gave his opinion on the diagnosis from the shop I took it to. If the compressor blew up it would of taken everything else with it, so he figured cut the belt before it does any damage to the rest of the components.

Sounds like either a water pump or a timing belt or tensioner problem. There’s a chance it is a sticky lifter too. Keep your eyes on the temp guage and the coolant level until you get this fixed. Hopefully nothing worse than that. Keep your fingers crossed. To isolate the location better, you could take a 3 foot length of garden hose and use it as a sort of engine-stethoscope.

@Paul, I hope he wasn’t just pointing out the “hole” in the top of your strut tower that the strut mount goes through, lol. In all seriousness, go with him if you trust him - not knowing him, however, I stand by what I previously said about this being bad advice for him to give you.

First of all, your mechaniic may be a great guy but I strongly suggest you look eksewhere. Use him for oil changes and tires if you’d like. Cutting the belt that drives the power steering pump and the AC compressor is a really bad idea. It robs you of the ability to make sudden avoiodance maneuvers (like if a child runs out on front of your car) and eliminates the ability of the defroster system to remove moisture. IMHO having these systems working properly is safety-critical, especially in the winter with so much driving to be done in darkness.

Bottom line: he failed to diagnose the probelm AND gave you very poor advice.

How “due” are you for havng the timing belt changed? How many miles does the car have on it?

You’re overdue for a timing belt, yet wondering about whining and knoxking. Both could be signs of a failing timing belt that’s possibly even jumped a tooth. Since this is an interference engine, meaning that if the valve timing is off the valves could kiss the pistons, it is imperative that you find a competant shop to look at it. If this is tha case, and it isn;t addressed, further damage can ensue.

Regarding changing the oil with synthetic every 3500 miles, I commend your efforts to pamper your engine, however you’re changing it far more often than necessary and with unnecessarily expensive oil. I’d suggest gioing to your owner’s manual and folling their advice.

In summary, your noise es are probably coming from that overdue timing belt, you need a new mechanic. And you need to get a proper diagnosis pronto, and you need to redirect the use of your resources to properly prolong your engine. The cash you’re speding on the excessive and expensive oil changes is better spent keeping up with things like the timing belt.

Fixed it, turned out to be the ac compressor the whole time. My mechanic made a mistake and told me the compressor was on the same belt as the power steering, it wasn’t. The compressor is on the belt with the alternator. He owes me a beer or two for that! I went to a awesome honda/acura shop in greensboro called “triad auto”, they quoted me the same as other shops $1400 for the compressor, dryer, reciever, flush, add freon, etc. They ended up putting a shorter belt and removing the compressor all together, saving me 1200 bucks :slight_smile:

I also posted the before video of the noise, sounded just like a water pump… hope this helps someone!