dgoodsy

I have a 2008 TL base nav auto 111000kms/70000mi. I was getting a low frequency (1, maybe 2 ticks per revolution if i had to guess) ticking/knocking noise in the engine, once the engine had been running for 10 seconds or so. The colder the start, the longer the engine would run quiet before it started to make the tick/knocking noise. The noise either goes away or gets drowned out at higher RPMs (2500/3000ish). I did some searching and discovered that the timing belt tensioner could cause a noise just like this. I ordered the aisin timing belt kit and installed it (no record of it being done by a previous owner so it was time anyways) but it made no difference in the ticking noise. I also installed new spark plugs at this time (ngk IZFR6K11) and noticed that the #5 spark plug tube seal was not sealing well and that coil/spark plug/tube was oily. there wasn't really any oil pooling at the bottom but there was enough everything dirty, which i cleaned this up as well as i could. the first start with the new timing belt/spark plug it started fine, but vibrated a bit for 10 or 15 seconds, then smoothed out. I could not audibly detect this slight rough running, but could only feel it through the seat. I figured it was something to do with the oily spark plug tube and since it smoothed out, i left everything as is.

It drove fine for the next week, no rough running or anything else notable other that the continued tick/knock.This past weekend i decided to measure/adjust the valve lash to see if any were way out of spec and causing the noise. (I also replaced the valve cover gaskets and spark plug tube seals at this) I ended up tightening up the lash on 8 intake valves. These 8 were quite a bit looser than the other 4 that were right in the middle of the spec. They are all now pretty near the middle of the acceptable adjustment. All the exhaust valves were on the tight side of okay, so I left them alone. In my mind this many loose valves should cause a sewing machine ticking noise rather that a low frequency tick/knock. I wasn't hopeful that it would quiet the noise i was getting and i was right, the first start showed the same tick as before. (It may be slightly quieter now but it is really hard to say). The power steering pump made a groan and something briefly squealed then maybe a slight pop before it quieted down to normal (my memory is a bit fuzzy on this but it seems to me that it was more that a groan and slight squeal) on the first start after the valve lash adjustment, (i found out 2kms later that the power steering hose started leaking at the junction where the hard line off the pump and the soft line started dripping pretty seriously. This may or may not be related to the power steering groan/squeal. I was gentle as always when i disconnected and tied this hose out of the way to do the timing belt work and the valve lash adjustment work.) The car did the exact same slightly rough running as it did for the first start after the timing belt change, and smoothed itself out again. I figured this was due to the still oily spark plug coil again. I only idled the car in the garage for a few minutes and then shut it off. The following day i went out and started the car and after a few minutes of idling i noticed the check engine light was on (not blinking). It started fine, and ran fine. I drove home (250kms/150mi) and all was good (except the leaking power steering line).

I do not have a code reader so i don't know what the code for the check engine light is, and i realize that limits how much anyone can help me too. I am wondering if there is something i might have unplugged that would cause a CEL. I did not disconnect the throttle body connector, however i did disconnect the evap purge valve, and the dual stage intake actuator. There was another sensor i unhooked near the throttle body too but can't recall for sure (probably MAP sensor, maybe coolant temp?)The battery was hooked up the whole time, but the key was never in the ignition.. should any of these cause a CEL without turning the key on while they are disconnected? I realize a really poor valve adjustment could cause a CEL but i figure that tightening up loose valves shouldn't.

In my mind i wonder if the (slightly) rough running on first start would have caused the CEL, but it seemed identical to the timing belt change first start that didn't cause a CEL...could it be something to do with the power steering pump groan/squeal/pop on first start? i know there is a pressure sensor in that pressure line...any other thoughts? (other than i need to get a code reader, i'm looking into them)

I have quit driving the car until i get the power steering pressure hose fixed, it makes a mess and leaking fluids in the engine bay is never a good thing.

Thanks all

nfnsquared

1. There is a safety recall for the PS hose. Pretty sure it covers 2008 models. Has it been done on your TL? (You can call any dealer and give them your VIN and they can tell you if the recall has been done.)

2. Re: the MIL. Yeah, there are about 11 things you unplug to remove the manifold IIRC. The MIL may or may not be related to an unplugged sensor.

3. Take it to any auto parts store and they will read your codes for free.

dgoodsy

1. Yes, I read about the recall and promptly booked my car in as soon as they could get it in.

2. Everything was plugged back in before the key was put in. I can see how those items being unplugged with the key on would cause the MIL, I'm wondering if any of those being unplugged even with the key out would cause it for sure. Surely someone here has done it the same way I did (battery connected but no key), and I would guess this isn't something that would be hit or miss.

3. Yes, I will be doing this once I get the car back on the road.

thanks

Pair of TLs

You can do #3 when you do #1.

dgoodsy

I checked and the dealer wants $90-$140 to scan, depending on what is found. For that price I will pass and get it scanned for free somewhere else this time. I can always go get the dealer to scan it at a later date if i need.

thanks,

dgoodsy

I rented a scan tool today, found code p0443 - evap canister purge valve circuit malfunction. I checked under the hood and found an unplugged evap purge valve. I don't recall unplugging this but apparently I did, and didn't do a thorough search of the area when I was "done". Anyways I plugged it back in, cleared the code and when I took it for a brief drive the light did not return. Seems like it is fixed.

As for the tick, it hasn't rectified itself. Any other suggestions?

dgoodsy

So i changed the serpentine belt this weekend and decided to run the car with the belt off to see if the noise changed. To my surprise it seemed louder with the belt off. I found it odd, but it seemed quieter again when the new belt was on. maybe this had to do with not having accessories producing noise to down out the tick more than the actual source of the tick getting louder.

I noted that when i started the car with the serpentine belt off (car was cold -15C/5F temp, and the car had been briefly idling a half hour prior) the noise seemed mostly normal, but as i was leaning over the engine listening the engine idled down and the noise seemed to get a fair bit louder.

I have also noticed that when starting the engine first thing in the morning (well below freezing temps) the tick is not there initially, but over the next 20 seconds it gradually appears. I briefly wondered if a crank bearing was worn, but the oil pressure light goes out immediately upon starting so i doubt it.

dgoodsy

Is there any other somewhat common failure point in the heads that would cause this noise? rocker arm shaft wear, rocker roller etc?

I should note that i have one intake valve that i tightened up the lash so it was within spec with the feeler gauge, but when i moved it with my fingers it felt like the lash was very loose. It felt much looser than the other intake valves that i had adjusted or verified in spec. I'm wondering if the rocker arm has a divet worn where it meets the valve stem, which allows lots of play between the valve stem and rocker arm but doesn't allow the feeler gauge to accurately show it.

Also i noticed that the rear head looks almost new with the valve cover off. There is next to no oil staining at all, while the front one looks much more stained. I'm fairly certain the rear head was replaced for some reason or another. I'm not sure of that is any clue as to what is could be ticking or not...

thanks guys.

thoiboi

I think you may be onto something in regards to the Serpentine belt. There's been a lot of issues with that tensioner as well. I'd try replacing that to see if the tick disappears.

dgoodsy

Just this afternoon I pulled the serpentine belt off the car again and started it. Again it wasn't warm, so it took 30 seconds or so, but the tick showed up, just the same as it does with the serpentine belt on.

I should double check all spark plugs, but this tick happened when all the spark plugs were tight prior to the timing belt change, and I changed the plugs with the timing belt too, and the noise didn't change. Still, just for my peace of mind...

redbeard1

Hello,

An auto stethoscope is usually very helpful in isolating the source of noises.


Good luck.

dgoodsy

I picked up a stethoscope as per redbeards suggestion. The sound seems to be loudest coming from the middle of the front valve cover. It was one of the cylinder 5 intake valves that had that felt loose moving it by hand but tight with the feeler gauge.I now feel confidant that is indeed my issue.

So, are replacements rockers available? I can't find them on rock auto. I know I could just tighten it up based on my feeling of the rockers motion, but that is no way to get an accurate lash measurement. are intake valves as sensitive to over-tightening as exhaust valves? I know over-tightening the exhaust valves lash would be bad news...

Will Y.

Have you replaced or tightened plug #5?
If not, check plug #5 to make sure it is not loose or backing out.
Plug #5 sometimes backs out and gets blown out of the cylinder head on the J32 engines; the loose plug supposedly creates a knocking noise when backing out, before the plug blows out.

dgoodsy

I did find plug 5 loose this past fall. I tightened it up, and it was still tight at Christmas time. I replaced all the plugs at that time and haven't checked them since. I'm fairly certain that's not my problem, especially since the sound was present after i tightened the plug the first time and also right after i installed all new plugs as well.

thanks for the suggestion,

05 Acura TL

To answer your question about the rockers being available, they can be bought from Honda/Acura, both as an assembly and individual parts.

For example if you go to acuraoemparts.com (vendor on the site) and put your car info in and go to Valve- Rocker Arm (there is a category for front & rear) you will find the prices & part numbers.

dgoodsy

thanks 05 acura tl.

I haven't done a lot of parts searching for this car yet so i am just getting familiar with how to find parts. that seems like a good source for parts, but is a little harder to navigate compared to what i have been used to with other cars.

Also for anyone else reading this with a similar issue, I found the following article on another cause of valvetrain noise. It is regarding the clearance between the rocker shaft bridge and the rocker shaft, just yesterday was the first I had read anything about it. If i cant get anywhere with the rocker arm itself, this will be my next item to look into.

https://www.tirebusiness.com/article...ocking-ticking

csmeance

check your crank pulley, the rubber can crack and deteriorate and cause noises! Also have you checked to see if your cats are clogged? Any tears/rips in the air intake rubber boot? They tend to crack and have unmetered air enter the engine.

dgoodsy

When the crank pulley was off for the tb change I gave it a brief look, nothing alarming stood out to me.

I haven't really considered my cats, I guess I could use the stethoscope to see if the sound is louder along the exhaust port down to the cat. For now I am really leaning towards the loose intake valve lash as the cause for the noise, but checking the cat with a stethoscope is a quick check I will do before taking off the intake and valve cover again.

​​​​​​ My car has an aftermarket "cold" air intake from a previous owner. It's a sore subject with me, I'm looking to replace it with the oem pieces. But there are no leaks in the boots that are on the intake I have there.

WDPanda

Is there a video of the noise?
i'm wondering if you're hearing the fuel injectors?