As the title states, my '04 Acura Tl has some issues with teccin'... As soon as I reach 3.5k rpms the car completely bogs. The engine completely pings as soon as i hit "vtec" range... Not only that but if i bring it up past ~4 (throttle response dies around 4, and then very very slowly creeps up to 4.5k..) metallic, clanging noises can be heard from the engine bay. MY suspicion is valve chatter... However, i took the car in to get looked at and my mechanic basically told me there's nothing wrong with it and that the engine was "pinging" because i'm not using premium fuel. Another symptom that has become apparent is my VSA light, sometimes it will come on and stay on for the duration of a trip. Any thoughts would be greatly appreciated but i think one of my cylinder heads is probably fucked and needs a rebuild(more than likely the head with the vtec cam); however if you have any idea or have experienced this before please give me your input.

 

is your oil low?

also; APP sensor can go bad.
(accelerator pedal position) which can cause the car to go into limp mode which limits vtec.

 

Oil is fresh, sits now at 97750, oil was changed at 97000.. Okay, as i was researching i also came across people saying vtec solenoids could lead to what i'm experiencing, views on that?

*a bad vtec solenoid

 

You don't have a magic VTEC cam in just one of your heads. There is one cam in each head, and each is technically a "VTEC cam". Each cam has three extra, larger lobes and each head has three extra rockers. VTEC is applicable to the intake side only on this engine.

If you're experiencing problems as low as 3.5k, I doubt it has anything to do with VTEC. What's your mileage? What, if any maintenance has been done? Also, you shouldn't ping too much on standard octane in moderate weather. The ECU should be able to compensate by pulling timing, resulting in slightly less power.

 

well why aren't you using premium fuel AND revving up that high?!

 

Lol, it's not going to hurt it if you go to redline on 87 or 89 octane.

 

97k, as stated above. 105k belt/w. pump has yet to be done. Always have used sunoco 93(closest gas station to my house, and more of a habit now since i used to have a 93 octane tune on my subaru). Yeah i don't understand why my car is pinging so hard, it doesn't matter the weather it was bad during the winter and still is bad

 

Any CELs? Spark plugs?

 

I agree. If your VTEC stopped working, the engine would just continue to run with the less aggressive cam profile. Your description of the symptoms sounds pretty scary - I'd try a different mechanic, and ride along with them for the test drive.

 

Sounds like the same problem another member is having, APP sensor?

 

No mils apparent, spark plugs... I doubt it.
I agree, I don't know that it's my vtec either. Here's a more in depth description of what happens to my car when you try to push it beyond 3.5k
1st gear I never take past 3 to start out..
2nd gear will rev out to about 4-4.5 then hits a wall, bogs down and a lot of clanging/chattering comes from the engine bay..
3rd gear will start to buck right around 3.5k rpms, when you get on the throttle the entire car starts to shake.....
4th gear 4k will cause the car to bog again
And so on and so forth...
I have noticed as well that the car does this no matter how much throttle you are giving it, it can be brought up to 4k rpms at 1/4 throttle and still exhibit all symptoms..
I believe my block is toast

 

Could you link me to his thread?

 

Also would like to throw out that when you push the car to these rpms it smells like a combination of running rich and a burnt cat..

 

Not much on it yet:
https://acurazine.com/forums/3g-tl-problems-fixes-114/traction-control-vsa-stuck-886645/

I used the search button:
https://acurazine.com/forums/3g-tl-problems-fixes-114/app-sensor-guaranteed-cr%40p-out-803593/
https://acurazine.com/forums/3g-tl-problems-fixes-114/replaced-app-sensor-today-817806/
https://acurazine.com/forums/3g-tl-2004-2008-93/my-110-000-mile-journey-cost-issues-beyond-704808/
diy?: https://acurazine.com/forums/3g-tl-problems-fixes-114/diy-app-sensor-730958/

Search Troll!

 

Maybe coilpacks or spark plugs figured I'd throw that out there.

 

Your app sensor wouldn't be causing those metallic sounds; which is your real serious problem. I'm not sure that I agree it's your block - sounds more like a moving parts issue.

 

It really sounds like my valves as it comes on right around 3.5-4k rpms but then again i'm not sure and i'm also aware that it's rather difficult to make a diagnosis via the internet

 

Maybe a failing spring or something?

if I were you, I would do a valve job, just to make sure everything is fine...also run some seafoam just incase...

double check your vac lines while you are at it

 

An adjustment or a head rebuild?

 

Troll, tough problem. If the rapping / rattling sound is indeed pinging valves, then something is broken. It could be mechanical: timing, valves (as Swoosh suggested), etc. or an electronic problem (much more likely): perhaps a bad anti knock sensor, ECU issue, or electronic distributor module problem. Bogging down in power sounds like you're not firing properly on all cylinders, which would also point to an ignition related problem. The other long shot might be a lean condition--this can also cause pinging, and power loss from a bad fuel pump, or clogged fuel filter.

A good mechanic who knows the car should be able to quickly diagnose it. I doubt you have to worry about "engine block" issue, unless you continue to drive it in this condition while it knocks and beats the bottom end. You don't have that many miles on it.

Please let us know how this goes.

 

Check for exhaust blockage, cat or muffler, then app sensor.

 

you sure you dont have a CEL?

from what everyone (including me) has mentioned, you should be getting a CEL...

 

It's almost for sure a plugged/broken apart catalytic converter. The converter will rattle sometimes even at idle when it breaks apart internally. The huge backpressure causes pinging.

If you have an IR temp gun, shoot the temps of both precats before and after.

If its not the cats check fuel pressure while under load.

For what its worth valve chatter is a made up condition. No such thing.

 

If its backpressure from a bad cat there might not be a cel. The ECU doesn't monitor back pressure, its not misfiring and even if the cat is non functional with enough restriction the secondary 02s are going to see the required change compared to the primaries. As far as the ECU is concerned everything is fine its just running on crap gas.

 

My guess as well...

Although, on my RDX there is an oil filter screen for the VTEC solenoid. If plugged there will be problems. Not easy to access on the RDX, not sure about the TL.

 

Precats? Meaning the cat in the jpipe?

 

^no, the catalytic converter on the front and rear of the engine.

 

Most likely those ^^

The 3rd cat can cause the same problems but it seems to hold up a little better than the precats.

 

I had the same symptoms with my 04. I found that the oil filter screen for the VTEC solenoid was clogged. I also found the EGR port was glogged big time. I pulled the manifold off and cleaned it out with carb cleaner (post with instructions including pics available by using the search tool). The manifold cleaning (EGR port) helped the most. The VTEC clog caused a turbo type effect on acceleration. It would bog first and accelerate hard afterward. Cleaning the screen took care of it for about two years. I found out I had grime in the engine and a change to synthetic oil broke it loose .

 

http://www.heeltoeauto.com/rv6-perfo...s-ua6-ua7.html
input?

 

Alright so after driving the car for a bit longer I do believe I have an issue with my cats. I haven't used an temp gun on them but my rear precat seems to glow after a long drive.... It's also noticeably hotter over my rear precat. What do you guys think about gutting the cats to see how that affects the issue?

 

If one is glowing and the other is not I would be worried about one being plugged or one getting a rich mixture/raw fuel.

 

Over the weekend I installed rv6s hfpc + j pipe as well as a type s exhaust. The issue has been solved, I found out that the 3rd cat was white and look pretty well toasted... The other two looked okay. Thanks for the help acurazine

 

Epic.

 

EPIC indeed....

thanks OP for coming back and updating us

 

Still experiencing some issues with my car; mostly suspension related however... I'll probably start a build thread (since it seems this car is going to require some work lol) Over the past two days I also put on HPS pads + stoptech slotted rotors. Brembos are a bitch to work on especially if the last person to work on them didn't use any anti-seize. Long story short the threads to mount the caliper are incredibly cross-threaded/fucked. Not only that but the bleeder valve got stripped on the same caliper (inside bleeder valve).... So i'm riding around on an absolutely horrible and unsafe brake setup. I need a new FR brembo ( or have it re-threaded by a machine shop ).. After I get my brakes set up correctly I'm going to put on BC BR's and a camber kit.

 

search around bro. you're not the first one with this problem
Same thing happened to me and a lot of other members with the BREMBOs,it's due to the dissimilar metals (Steel bolt + aluminum calipers). I ended up buying time-serts from belmetric.com. I think they were : M14x1.50 x17.8mm

Good luck.