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During first start of day, car rumbles noticeably. Like an exhaust leak. Noise isn't an issue, not so much loud as it is a physical rumbling. Feel it predominately "under my feet" / "under the floor". Gets better after warming up and drives perfectly without issue. Strong! No misses or lagging or noise.
maybe related / maybe not: vibration noise when at idle...basically on the dashboard and steering wheel. Noth8ng visible, just more a sound.
Thinking this started after all I did with fixing recent egr insufficient flow. As you may recall, when cleaning the ports, ALOT of water and cleaner went down the exhaust opening (on egr port housing, left of the egr port hole). Not sure if related.
Hey did I mention.....some idiot backed into me while I was in park. Yep. Was waiting in line to get gas....some dope tried backing out of her spot and went right into me. Dented my back door really good. Her insurance sent a check, now I need to fix. Ughhhhh.
Just a strange thought, have you tried using some dry gas in your tank just in case some water vapor got into the fuel system? Probably wouldn't show up when running at a higher RPM but at a an idle it would be more noticeable.
Does this always occur when the car is cold or does it also occur after the car is driven and then sits at an idle? At an idle the Idle Air Control Valve (IAC or IACV) controls the idle, it is a finicky unit and not a part that aftermarket units are very successful in working well. The OEM part is about $300. I have tried multiple version of the aftermarket parts and took them apart and the OEM is the best built unit but I couldn't identify why the aftermarkets performance is so bad compared to the OEM. Hopefully your problem is not the IACV.
I replaced IACV several months ago, with Honda genuine (expensive) part.
issue/rumbling is during cold start.
UPDATE: last night, had car parked outside while in casino. Came out, about 55 degrees, car rumbled more than normal. Even when I gave it gas (in park), it "missed". This was new. Even my wife noticed it, and she normally says things are in my head. Ha! It was to the point where I waited for a CEL to give me a clue. Light never came on. Car warmed up so I drove home without issue. I did not get the dry gas yet.
I know if this was engine coolant temp issue or ignition coil issue, I would get a CEL.
But what if issue is exhaust related (something non cat system related) or valves need adjustment? Would a CEL come on?
My thought is that it's exhaust related.......exhaust smell is present. May be best to have full exhaust system inspected.
was preparing to go on an errand, started the car, but the rumbling seemed a little worse and then we heard a KNOCKING sound. Wasn't very loud, but noticeable. So drove my sons car to where I needed to go.
got home, added drygas and started car. Heard the knocking sound again. it isnt constant knocking sound. I tried to learn more about the sound and it appears to be coming from the cat converter or area. As I looked underneath it appeared more obvious that the knockinv sound was coming from there. It also made a rattling/clunking noise when I turn vehicle off....noise by the cat or more so down the exhaust line by the muffler.
After doing some reading and watching some videos, I am thinking a cat converter, or both, is in my future.
PROBLEM: I can only afford after market and i have ZERO idea which ones to buy on Ebay. I believe there to be a middle cat and a rear cat. Some say illegal in California. If my car is CA emmissions, will the EPA compliant (not allowed in ZCA) not work or fit in my car? Yikes!!!
Some other cars (like the 3rd GEN TL) have 3 cats, 1 on each of the outer banks of the engine where your exhaust manifolds are and then one downstream of the JPipe.
I would NOT buy stuff like this one eBay. Make sure you get one of the CARB compliant ones. Also make sure you get replacement gaskets (#16/#17) on the first page.. I like OEM personally but you're welcome to get aftermarket ones from Rock Auto as well.Note that they are difference sizes
Obviously the CAT is expensive, so be sure you need a new one before you replace it. A while back I had a problem with some rattling and some thumping noise and I found the exhaust pipe going into the front of the muffler was broken loose on the inside of the muffler (so you can't see any damage). This pipe being able to rotate inside the muffler allowed the muffler to move up and around causing the rattle and the occasional thumping noise. The rubber mount held it up but it was still moving around. Replaced the muffler (has the pipe attached already) and that problem went away. You might want to check there. The muffler really shouldn't move.
Another check requires that you have an OBDII reader and if you don't have one that should be your first purchase. They cost anywhere between $30 and up, you need one that can report O2 sensor data and running data such as fuel trim data, as well as errors. Anyway, if you look at the O2 sensor data, the values you see there you can help you tell if the sensors are working. The upstream one should be fine as it is before the the CAT; if the downstream one is not showing good data the CAT maybe worn out or damaged. If the pipes going to the CAT are broken they can be welded. These would be steps I would take before spending money on a new CAT.
Also, the valve lash adjustment is a good idea as the exhaust valves tend to get a bit tight over time and should be checked. I would do all these things BEFORE I considered replacing the CAT.
Thanks, everyone. Will do as you recommend.
between this issue, the valves never being adjusted, the dent in the back door due to recent accident where someone backed into me, the oil pump seal leaking............I have to consider perhaps looking into another acura or honda......
the experience of purchasing a newer used car is NOT pleasant.
hey @Domenic Ricci I just don't see how you can need a cat without any kind of CEL's pointing to that. any chance you can record a video showing the sound you are hearing?
Exhaust system is rusted out, basically. Cat appears OK, no CEL. Knocking noise (which hasnt come back in a few days) is most likely an internal part of the Cat breaking off. Mechanic said if I wanted to the work it would have to go to a specialist shop, because he would have a hard time doing that type of work. He said what it needs would be considered extensive, and wouldnt be cheap.
He said the rumbling and vibration at idle is also part of the motor mounts being shot. Needs all new mounts.
So the open items list is: Exhaust overhaul, motor mounts, struts, oil pump seal, rear door repair/replace with junkyard door. 240K miles. Tranny was rebuilt at 170k. Car is 24 years old.
Mechanic said it may be time to invest in a newer Acura TL, versus putting money into this one. Not a rush, though. No engine light. And no degradation of performance. Car drives very well. No misfires. No CELs. No rough shifting. No slipping. Give it gas and it takes off like a bat out of hell. Also does a good job with Uber Eats deliveries. Its tough....can take a punch.....can take the stop and go. Mechanic said engine is strong......he likes the TLs.
I will keep my eyes open for a newer TL. My concern is: I need to get at least a 2009 or 2010 (I forget which year),,,,,the year when the Honda transmission issue was remediated. I already had my current 2000 tranny rebuilt, I do not want to rebuild another one ($3k+). Do you know which year the transmission issue was fixed? And for that matter, purchasing another TL means I would have to perform the timing belt kit job. Unless, of course, I had evidence from the seller that they changed the belt recently. From my point of view, you dont mess around with that when you purchase a used TL.
I would be sure to have that job completed, and I would also start doing 3x3 transmission fluid changes.
That is the latest. For now....it is gas up and go. Keep CEL off. Fingers crossed!
That sounds better. The CAT can have pieces break off and sometimes it gets clogged. See pictures below. Good unit Bad Unit
FYI you can clean out your CAT. There is multiple methods such as, remove and soak in dawn dish washing detergent or some other degreaser. There are some fuel additives that are supposed to clean out the CAT. If you have no black smoke or rotten egg smell it is problaby ok but dirty.
The problem with the exhaust being rusted out is which pieces(s) are rusted out, some parts are available some are discontinued and would have to be made at a shop or located at a yard. See diagram below, what pieces are bad?
Motor mounts are relatively easy to do, although the rear mount can be a pain to get access. These you can get through Rock Auto.
Mechanic didn't say which parts specifically, he just said the exhaust is a mess and some of the parts (like you said) aren't, made any more. He said if no engine light, no smoke, no loud noise, no engine performance issue - best to leave it alone and consider a newer Acura.
That was his main point. It may be time to find a newer model. I'm worried about getting a 2000-2008 (think they are the years) because it may mean i will do a rebuild.
I did motor mounts in 2000. Aftermarket. Labor was $300. Guess I got my monies worth. Problem with motor mounts - you get what you pay for and the Honda oem mounts aren't cheap.
And again, I need body work on back door, could get dent pulled or get door from junk yard.
Things are adding up....... where do I put the funds? Current vehicle or something newer?
I can tell you what I would do but I would be doing the work myself which is much cheaper. If I had to pay someone to fix the car I would probably be driving it till it stops and saving my money for another in the meantime, I am a little confused by your mechanic; if you paid him to look at the car he should have given you a list of the parts that need replacement. If he didn't charge then I can almost understand. Drive safe.
Mechanic didn't charge me.....just a quick lift and go. My main concern was the cat (because it would affect me being able to get car registered in NV), which appears to be OK.
I actually think the dry gas helped. I also have not heard the knocking noise (from exhaust area) anymore.
So without a CEL, smoke, loud noise, misfiring....I think I am ok to just leave the exhaust. Car runs strong!
My main "annoyance" is the vibration. Mechanic said this is thr mounts. Thinkin of getting this handled. Question: are there any aftermarket mounts that could work? My thinking is the expensive OEM are much superior. Anyone had luck with aftermarket? Maybe I search RockAuto.
Then, I will need to move to fixing dent in rear door. May be easier and even cheaper to get door at junkyard.
Then maybe 2025, repair oil pump seal leak (maybe I'll be due for timing belt job again). But I just went 3k miles since last oil change, and despite leak (garage floor, yikes), I didn't need to add oil.
About 2 years ago I put in all new mounts from Rockauto and they are the Beck/Arnley brand. I have had no problems with them and since it definitely took out the vibrations at idle, The front and rear mounts have a vacuum inputs that the car uses when at idle and tightens up the mount and you have less vibration. The right side mount (by the timing belt area) doesn't get a vacuum. There are also mounts for the tranny. The rear engine mount is the hardest to replace as it is a pain to get to but if you decide to do it yourself the front and right side are simple. You can find YouTube videos on all of it. Here is the Rockauto link for a 2002 TL or TLS. I don't remember your car's year.
I agree with your mechanic that the OEM are probably better but in longevity and I doubt you will have the car in 10+ years, so why spend the extra for OEM. On Rockauto they don't sell a B/A kit they sell them individually; you need a right, rear, and front. Here is the link. if you want the tranny mounts you will need a front and rear. Here is the link for those. Also for your information the units that are marked with the heart means that rockauto has had less problems with those items. The links should take you to the parts for a 2000 TL.
I used B/A as I am more familiar with them then the others. If I was to buy a kit I would get the kit from Anchor as two of the units in their kit are marked with hearts (as an individual part number) on Rockauto which means people have had less problems with those than others. It is also $7.10 cheaper. Also don't forget to plug in a discount code in the " How did you hear about us" box here is a code 259424558231646186, should get you 5% off. These aftermarket units should get you about 6 years +/- 2 years.
noise is familiar as when I removed the egr valve and started vehicle (when cleaning egr port). Today I noticed the egr valve was loose/not snug, and it also looks discolored, so I removed it and cleaned it. I also cleaned/flushed the egr port again (was dirty again).
is noise internal engine? Is my engine toast? Exhaust related? Need oil change (I'm at 5k miles) and higher octane fuel?
note: ZERO performance issues, no engine lights, no stalling, no hesitation, no misfire, no smoking, no overhearing, etc. Thank you!!!!!!!!!!
It the ticking is louder by the driver's side firewall it is the Evap Purge Solenoid (see picture below). If it's from the engine itself it could be multiple items, low oil, timing belt, bad plugs, loose or damaged valves, even pistons being loose (although with that you should see some black smoke from the exhaust), Exhaust leak (specially if near the engine itself). The bad knock sensor could cause a noise but mostly it would cause vibrations since it is not working. A lot to remove to get to it on these cars but I have replace mine since it was broken in half.
That EGR valve is interesting obviously having been exposed to a lot of heat.
Also interesting is the ticking on the recording seems to decrease as the car warms up. If this is true I would be thinking lack of oil in the upper intake manifold for the valves. First thing I would check is the condition of the valve ends, and rockers and rocker arms. Look for evidence of overheating, lack of oil, discolored components. I would also check the valve lash adjustments. If I saw indication of lack of oil look for clogged oil passages if not clogged I would be considering a new oil pump. Of course eliminating plugs, and exhaust should be easy by visual inspection and checking the torque on the exhaust manifolds.
Car will require a trip to Acura dealership service or local Acura mechanic. Noise does seem to be less as car warms up, but still exists. My gut tells me thus is exhaust related but I am uncertain. Yesterday filled tank with higher octane and changed oil.
strange car. No engine lights. No performance issues whatsoever, even with my AC cranking (112 degrees in Vegas today). But that knocking / clicking is upsetting. Stay tuned.
Since the noise decreases when it warms up, that would make me think that more oil is flowing into the rocker assembly or there is a expansion that is sealing up a gap, maybe at the exhaust manifold gasket.
It could be the gasket it could be the manifold isn't torqued correctly, it could mean there is a crack in the manifold, it also could mean that noise isn't coming from the exhaust.
Not sure what that sound is.
Without being there to try and isolate just exactly where the sound emanates from is tricky, especially without any DTC's.
Maybe make sure the egr is torqued to 15flb-ft with a good gasket?
Noise appears to come from top of intake area, close to throttle body area.
doesn't sound like it's coming from timing belt side.
noise also sounds different when in car sitting at idle. I think the noise travels down to underneath the vehicle, like noise ratting from the cat or area. Maybe separate issues, not sure.
NEW ITEM I JUST NOTICED after driving around in the 298 degree heat. Coolant fan overflow tank is boiling (fluid boiling).
no engine lights. Car runs fine. How does this male any sense?
i would be interested to know how a bad cat makes that noise.
Mechanic said parts of the cat (inside) are broken off and making the noise. He brought me under the lift and moved the cat up and down (banged with hammer, too) and the sound was the sound. He said after doing compression test and putting car on diagnostic machine, he said no engine issue. Said noise is radiating/traveling and that is why it sounds like it's coming from engine. Also, engine has no performance issues or engine lights.
well see. Hope he's right. Buying cat on rockauto.
03-02-2024, 02:01 PM
