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Old Jun 8, 2024 | 03:48 PM
  #41  
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Also, besides replacing oxygen sensors, is it proper to also change the spark plugs, too?
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Old Jun 9, 2024 | 11:45 AM
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Originally Posted by Big Dom
Also, besides replacing oxygen sensors, is it proper to also change the spark plugs, too?
how many miles on the current set
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Old Jun 11, 2024 | 02:24 PM
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Originally Posted by thoiboi
how many miles on the current set
17k miles ago
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Old Jun 14, 2024 | 07:26 PM
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Car fixed. Noise 100% gone. New converter from rockauto did the trick!!!!!
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Old Jun 14, 2024 | 10:18 PM
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Congratulations. I understand how the the internal part of a CAT can break up but to have made such a rhythmic noise I wouldn't have guessed.
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Old Jun 16, 2024 | 04:44 PM
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Originally Posted by Jon M
Congratulations. I understand how the the internal part of a CAT can break up but to have made such a rhythmic noise I wouldn't have guessed.
Cat noise is gone. You should heard the old cat....when mechanic shook it, it made lots of noise. Yikes! But glad the rock auto cat fit perfectly.

However, noise from engine is still there, though not as loud. Gets better after warms up.

OK so let's think. Probably needs valve adjustment. Exhaust valves. God knows what I did when I had water go down into the exhaust port hole when egr valve was off.
OK so if I don't get them adjusted soon, how bad is that? About $600 at dealer?

internal engine damage? Ok,then why ZERO performance issues? No check engine lights.

timing? I've had a bad timing belt tensioner before. Not same noise. Noise also seems to come from area around throttle body, versus other side where timing is.

Instinct, from my stupid self, says this is exhaust. From manifold or something.

will send video to mechanic tomorrow.



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Old Jun 16, 2024 | 05:06 PM
  #47  
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Also.....240k miles....never had valves adjusted. I really think this is the issue.
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Old Jun 16, 2024 | 06:52 PM
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A valve adjustment will probably run about $350 but that is guess from the internet. Obviously, I can't hear what you hear but a slightly loose valve is better than one that is too tight. After 240k miles yes it probably overdue for an adjustment. Most find the exhaust valves tend to get tight over time. If the noise is a ticking sound that is near the throttle body I would listen closely and feel around the Evap purge valve to see if you can feel the ticking (see my previous post in this thread on 6-5-1024), It is located by the driver side firewall about 8 inches from the side panel, has the hoses attached, should be right there for you to see. Did you ever replace the motor and tranny mounts?
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Old Jun 17, 2024 | 03:17 PM
  #49  
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Never replaced the mounts. Honestly the cat converter decreased the vibration I was feeling.
acura says $625 for adjustment and new valve covers.
Texted my mechanic for his price. No response yet.
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Old Jun 17, 2024 | 04:11 PM
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Wow. Can't believe that price. New valve covers????
You do know that the motor and transmission mounts are what holds the entire engine/transmission assembly in the car? I would do that before adjusting the valves.
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Old Jun 17, 2024 | 05:20 PM
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Originally Posted by Jon M
Wow. Can't believe that price. New valve covers????
You do know that the motor and transmission mounts are what holds the entire engine/transmission assembly in the car? I would do that before adjusting the valves.
typo. Meant to say valve cover gaskets. Sorry.

I can't see any way the noise is motor mounts. I understand the power brake test to see how much engine moves. Yes, mine does move. But there are NOT other symptoms of bad mounts (I've had bad mounts, this set was installed less than 75k miles ago). Symptoms, maybe hard to explain but.......like when I pull up into my garage and give it gas, you feel the engine move, almost like a bang noise (again, hard to articulate). Or the other symptom of when coming to a stop, you feel that slight jerking forward feeling and u say to yourself (with was that).

I took a video yesterday.....not much different from before. Also, noise almost goes away when engine warms, which I don't think would happen if it was mounts.

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Old Jun 17, 2024 | 06:42 PM
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I was not referring to any noise but as a repair to me the safety and performance of the car would be better served by replacing the mounts. I once had a 69 Plymouth where the mount busted, the engine torqued, and the vacuum line to the brake booster was pulled off and I went from having normal brakes to little brakes while basically standing on the pedal. Not a great experience.
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Old Jun 21, 2024 | 01:55 PM
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Fast update. Ran engine cleaner through engine oil (Berrymans 12). Drove 10 miles. Changed oil. Noise still present. Zero performance issues. No check engine light. Still thinking this noise is exhaust related (not sure why my egr valve is so discolored), but I understand the noise sounds like valves. Will get to mechanic soon. Just busy lately. Thank you!
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Old Jul 15, 2024 | 12:28 PM
  #54  
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UPDATE

well, not much of an update. Tapping/knocking still present at cold start, yet still no performance issues. So....I have been driving without issue. I still have to get to mechanic, but it's been hotter than hell here in Vegas and I haven't felt like driving much.
however, yesterday I checked the oil (1k miles)....full, very clean, oil looks brand new.



power steering fluid down. Ughhhh. Will top off today.

While under the hood, the battery cables caught my eye. Discolored!! Never ever saw anything like this before. It's been hot here in Vegas....118 degrees, one day hit 120 degrees. Is that what caused this discoloring? What in the holy hell? Should I take any action?

thanks!!!!!!!
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Old Jul 31, 2024 | 05:31 PM
  #55  
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Originally Posted by Jon M
A valve adjustment will probably run about $350 but that is guess from the internet. Obviously, I can't hear what you hear but a slightly loose valve is better than one that is too tight. After 240k miles yes it probably overdue for an adjustment. Most find the exhaust valves tend to get tight over time. If the noise is a ticking sound that is near the throttle body I would listen closely and feel around the Evap purge valve to see if you can feel the ticking (see my previous post in this thread on 6-5-1024), It is located by the driver side firewall about 8 inches from the side panel, has the hoses attached, should be right there for you to see. Did you ever replace the motor and tranny mounts?
Jon - let's say the noise (still present at first start) is due to a needed valve adjustment, by now, would I be getting other symptoms? Engine lights? Noise still there......still runs great. Me thinks I need exhaust manifold job..... maybe when I cleaned the egr port (remember, got water) I screwed the gaskets?
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Old Jul 31, 2024 | 05:36 PM
  #56  
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maybe next month.......mechanic says it's an all day job......

My next wish list item is oil pump seal replacement to stop the leaking. Though I just hit 1k miles since oil change and perfectly clean and full. Just looks like grim death underneath. I guess I would replace oil pump too, not just the seal? And yes, I know I would also do timing belt kit (water pump too)......

2024 goals......
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Old Aug 2, 2024 | 12:42 AM
  #57  
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I see you like to replace everything. If there was noise coming from the exhaust it either has a leak, something inside, or is moving around. You should be able to smell a leak, there shouldn't be anything inside as when you had the CAT off the mechanic should have checked to make sure there was noting inside the intake and down to the mufflers, they should have been perfectly clean. and the mechanic should have checked both visually and ran some rags through. The only place I have had movement on mine was a muffler had the internal weld break where the pipe goes into the muffler. The muffler was able to turn around the pipe. Replaced the muffler and the rubber holders and problem fixed.
If the exhaust manifold gaskets were hosed, you should smell a leak or have small movement when cold. When the car is hot the seal should be tighter.
If you look at the engine while idling and you see movement that will make a noise. I am a firm believer in having the engine and transmission actually connected to the frame of the car. Helps to keep it out of your lap if there is an accident. Also makes for a nice smooth idle and ride.
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Old Aug 10, 2024 | 04:29 PM
  #58  
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Originally Posted by Jon M
I see you like to replace everything. If there was noise coming from the exhaust it either has a leak, something inside, or is moving around. You should be able to smell a leak, there shouldn't be anything inside as when you had the CAT off the mechanic should have checked to make sure there was noting inside the intake and down to the mufflers, they should have been perfectly clean. and the mechanic should have checked both visually and ran some rags through. The only place I have had movement on mine was a muffler had the internal weld break where the pipe goes into the muffler. The muffler was able to turn around the pipe. Replaced the muffler and the rubber holders and problem fixed.
If the exhaust manifold gaskets were hosed, you should smell a leak or have small movement when cold. When the car is hot the seal should be tighter.
If you look at the engine while idling and you see movement that will make a noise. I am a firm believer in having the engine and transmission actually connected to the frame of the car. Helps to keep it out of your lap if there is an accident. Also makes for a nice smooth idle and ride.
Hi Jon! Hope you're doing well.

I never heard bad motor mounts making that noise (a noise which goes away 1-2 minutes after warmup). Also, no other symptoms of bad mounts is present (though I'm not saying the mounts are perfect).

my two questions are: if the noise was valves needing adjustments, and though with no engine performance issues, is neglecting to care for the noise leading me to future issues? I've been IGNORING the noise because it goes away AND it runs perfectly.
second question - did you see my posted photos of the egr valve AND battery cables discoloration? Looks like they both experienced extreme heat? Never ever saw anything like that before. Ever. 😀
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Old Aug 10, 2024 | 05:38 PM
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Hi,
Back in March you said the mechanic told you the mounts are bad.
He said the rumbling and vibration at idle is also part of the motor mounts being shot. Needs all new mounts.
IMO if the noise is coming from the valves when they are cold and goes away when they are hot they are probably not too badly adjusted. As I said previously a little loose is better than too tight. Generally, on these cars the exhaust valves get tight over time. As I like messing with this stuff I would check them and adjust if needed but I would do the work myself. Does the noise justify this, I don't know, someone would have be there to hear it themselves. As it goes away quickly I doubt it is something to worry about. The valve clearance should be inspected every 7 years or 105k miles. How is that for leaving it up to you?


The EGR valve definitely looks heat stressed to me. I also have never seen one like this before. To me this means the engine was extremely hot, Maybe due to the CAT issue there was pressure build up causing the EGR to overheat but I really don't have any previous experience with an EGR that looks like that. The battery cables are the same, it almost looks like gold paint on the cables I have never seen that either. If it is due to heat I would have expected melted wiring cover and discolored copper wiring. It would have to been pulling a lot of current for a quite a bit of time.
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Old Aug 10, 2024 | 06:14 PM
  #60  
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Thanks, Jon. Mechanic did say mounts were bad, but it seems like the vibration or whatever got better when the cat was replaced. Thinking mechanic is overstating the mounts....sure they aren't new....but they aren't that old either.

strange car! Strange owner!

right now I'm dealing with low beams. They turn off. They turn on. Now one won't stay on. Purchased star bit screwdriver on Amazon which is needed to loosen ballast cover......will poke around when the temperature goes below hot as HELL here in Vegas. Been using high beams....and been getting dirty looks about it.
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Old Aug 12, 2024 | 01:10 PM
  #61  
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Originally Posted by Big Dom
Thanks, Jon. Mechanic did say mounts were bad, but it seems like the vibration or whatever got better when the cat was replaced. Thinking mechanic is overstating the mounts....sure they aren't new....but they aren't that old either.

strange car! Strange owner!

right now I'm dealing with low beams. They turn off. They turn on. Now one won't stay on. Purchased star bit screwdriver on Amazon which is needed to loosen ballast cover......will poke around when the temperature goes below hot as HELL here in Vegas. Been using high beams....and been getting dirty looks about it.
replaced low beams. Wasn't that bad. Although both low beans aren't pointing the same. I feel like the driver side is pointing higher than passenger side. Not sure I feel like or know how to correct.
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Old Aug 12, 2024 | 01:59 PM
  #62  
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Scratch that - I think I fixed it. I was determined!!!
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