dillonkennedy003

Hi all,
I've been having an incredibly weird problem with my MY03... A while back I crashed the car (minor) and let it sit for a few months because shortly after the crash I had to go to college (August 2016) the car sat until winter break (December 2016) and it hasn't been the same since. Although I fixed the body panels and my car looks good once again, the engine would give me an issue where it would only rev out till 8500rpm and then make a noise similar to the noise it would make if one tried to hit VTEC before the car was fully warmed up, also under 8k RPM the engine feels the same way it always has, VTEC engages normally etc however above that 8K RPM threshold the engine feels extremely weak. I also would get an occasional random misfire code, I do not remember the specific code that was thrown. In December, prior to me even noticing the problem, I attempted a valve adjustment, I have since checked the clearances to make sure they are within spec and they seem like they are. Perhaps I've messed something up? Would poor valve adjustment cause these issues? The engine was not damaged in the crash, I redlined it minutes after and it was absolutely fine. Fast forward to the present day, I am getting slightly different symptoms compared to those I was having in December. The car will now go all the way to an indicated 9k RPM, but then will make the aforementioned noise, the car does not feel as weak as it had in the winter, but there is still obviously a problem. I am not getting any check engine lights.

Things worth mentioning:
-The car has 176K miles
-Original ignition coils (Could this be an issue?)
-Spark plugs changed at 143K miles
-Engine has no modifications aside from a Berk HFC
-Oil is topped off, changed every 5k miles (Mobil 1 High Mileage)
-Clutch only has around 20k miles, still grabs really well
-Had my fuel pump tested, it is within the normal range
-New Air filter 5K miles ago
-Brand new primary and secondary O2 sensors, problem occurred prior to this

I'm really at a loss here, I think it could potentially be a timing issue (Can timing chains wear out over time?) or a fuel injector issue but I'm not knowledgeable enough to know what is really causing this. I have repeatedly redlined the car just praying for a check engine light to no avail. PLEASE HELP!!!

Thanks,
Dillon

B serious

Is anything clogging the intake or exhaust?

Car Analogy

Yeah, car sat, mice made a home?

dillonkennedy003

Not that I know of, I could try getting a new air filter because while the car sat it was exposed to the elements. The hood was dented in such a way that it would have been possible for water to enter the air box. I might try to go redline the car without the air filter on and see what happens. With regards to the mice, where would you expect them to be? If they got in the exhaust, I'd smell them burning. I guess it's possible they got into the intake, but I don't see any evidence that would lead me to believe that happened.

What do you guys think? Moist air filter?

Car Analogy

They make nests, using all sorts of stuff. A neat could be clogging up your exhaust.

If there is anything wrong with airbox or filter it should be physically obvious.

jyeung528

well, i'm not sure what noise you're describing, what noise does the car make when you vtec on a cold engine? are you trying to describe the rev limiter kicking in?

the car doesn't make more power past 8k anyway, so i'm not sure what you're feeling regarding it being anemic. if the engine still spins up to 9k, it's doing pretty good, no?

you're able to redline, you have no check engine code. i think you're good to go.

dillonkennedy003

I know for sure that something is not quite right. Normally when the car redlines, it will bounce off the rev limiter. I'm sure you are all familiar with this sound. At the moment, my car does not bounce off the limiter, it simply just makes the attempted Vtec before warm noise if I can call it that. I would not recommend trying to replicate it, but instead of a boucing noise, it makes a constant noise that doesn't "bounce" and it sounds vastly different than the normal engine note. I'm begining to think the mice idea isn't so crazy after all. I don't foresee the mice getting further than the muffler but by no means is that impossible. I will check right now to see if the flow is different between the two mufflers, if so then I think there's probably a mice problem but if not I still wouldn't rule it out entirely. I will post back momentarily.

dillonkennedy003

The exhaust seems to flow evenly. I hate diagnosing things

Chuck S

VTEC gaskets and screen all good. (Wild guess.)

-- Chuck

Halfassjack

Check fuel pressure again when problem happens. Also test rate/volume.