Hey I know I’m new here but I’ve been checking this forum out for a few weeks now. Just got a ‘’21 Aspec 3 weeks ago and already started putting some personal touches like tint and black out badges.

All my past vehicles were lowered with an intake exhaust and tune. This vehicle will be no different lol.

The part about the intake not being made for the rdx is a real bummer. I could not accept that so I started doing some research and found that the MAF sensor for the 18-21 Accord 2.0t is the exact same part number as the 19-21 rdx.

I figured same maf same engine everything looks the same so I bought an AEM intake for a 18-21 accord 2.0t. Install went super easy. Everything bolts up perfectly except for the heat shield. It’s too large for where it needs to sit. So I used the lower portion of the stock air box as a heat shield and to support the AEM intake pipe. Maf bolted right up too.

I started the car and idle was perfect. Gave it a few revs and I could not wipe the smile off my face. Exactly what I wanted. Whoosh and psshhh! Car felt more responsive down low and the spool noise was amazing.

But… like others have mentioned, within 25km of driving the dash lit up with 9 warning lights. Not sure what the ecu didn’t like but it didn’t like the intake at all. Car still drove perfectly mind you with all the lights on. No limp mode. No hesitation. No shuddering.

check engine light
power steering light
traction control light
brake system light
collision mitigation light
road departure light
awd light
brake hold light
hill assist light

Ecu must have seen more air volume and it didn’t like it? Idk. For the accord it says no tune required. Not sure why all those other lights came on. What does an intake have to do with collision mitigation?

Anyway this was just more as info and thought I would be the guinea pig and try it out. I guess I’ll save the intake for when I get a tune.

 

Short video of revving

 

Just wanted to add that after I put the stock air box back in, all the warnings went cleared within 20km of driving and turning the car on and off a few times.

 

The part number for the MAF being the same is not relevant. The size of the MAF housing is what the MAF is scaled to in the tuning. If it's not the same size as the factory RDX it will throw fueling off. Too much correction either direction and the ECU will error. Those warnings lights appear when there's an error code present.

You should really check the error code. Likely too lean or too rich. If you have a tuning device you can get a custom tune for the intake.

 

Yes I realize that now. I have to take measurements still but I think the AEM pipe is a tad smaller than the oem housing. I’ll take some measurements tonight.

 

So I took measurements. The stock maf housing is almost 3.25” while the AEM pipe is 2.75”. Is that enough to piss of the ecu?

 

Also it seems counterintuitive that a "performance part" should have a smaller ID in that location. Do they advertise it as something meant to enhance low end torque instead of top end hp?

 

I guess it’s the same or larger diameter for an Accord. If the pipe is the same size I guess it won’t need a tune. That’s why they advertise it as no tune required on an Accord.

 

Rdx and accord have different ecu strategies and mapping- you can’t run the accord housing with a custom tune
they are not the same MAF housings
so far the best is the stock rdx airbox with a cold air pipe routed to it from the battery box air tube grille

 

I ordered a spare stock air box lid from Acura for like $35. The maf housing Is a tube that extends into the box lid. I’m thinking to cut it out and separate it from the lid and use essentially the oem maf housing and put an open cone filter on the end and see if the ecu likes that.

stock maf housing stock maf location stock size piping. In theory ecu should be happy with that no? I just want some sound and it it pics up a few hp that’s cool too.

 

I’m gonna try using the oem maf housing and separate it from the air box lid. It’s a tube that extends into the air box lid. Put a cone filter on the end and see if the ecu likes that. I ordered a spare air box lid from Acura for $35.

im just looking for sound really. Everything oem just with a cone filter. In theory it should work no? Lol

 

Sorry for double post

 

For sound-you need to remove the resonator on the air box

 

I tried taking out the snorkel box and scoop and I really had to strain my head to hear it.

 

The stock intake tube has resonators built
in also
the stock turbo is also very quiet
not much nois from stock system- it’s all designed to be quiet-
my big turbo and modified airbox are so loud I need to quiet them down-sounds like a 747 taking off

 

That’s mint 👍🏻

 

Brother I'm not clear on what this is. Can you give a bit more info?

 

the battery box on the rdx has a fan and a cold air duct that runs from the left grille below the headlight
what I did was reroute the duct, drill out a few more air holes in the grille and installed an insulated 6 inch air duct pipe that leads to the airbox, which I had already opened up the inlet hole to 5 inches-
i can attest that the inlet temps are within 5 degrees of ambient air temperature at all times

 

I'm depressed, I really want this to work. new owner and can't believe there's no option

 

get a big turbo and prl inlet pipe-
sounds like a 747 spooling and taking off

 

You can’t mess with the MAF leave it alone-
its big enough to support well over 400 horsepower-
If you want noise only without a tune the loudest I’ve found so far on a stock turbo is a prl intake tube for an accord with a kn filter -get rid of the airbox resonator and cut the opening to the airbox to 4 inch hole-
the bypass valve discharges into the air inlet pipe not to the atmosphere so there’s not much
“whoosh” sound-
the stock turbo is made to be quiet and the plastic intake tube going to it had built in resonators-
I did try the accord MAF sensor housing and an open element cone filter and there was some noise like you want but the intake temps were way too high for me

 

is this the right kit to order that won't throw any CELs ?

https://prlmotorsports.com/collectio...-intake-system

I wonder if its possible to run this other kit - but take the lid off the top of it so the cone is exposed:
https://prlmotorsports.com/collectio...-intake-system

anyone have either of these ?

 

Can I just pay y'all a compliment on how smart, and adventurous you are!!! WAY---OVER---MY---HEAD.

 

I have both kits-
the intake tube works with a tiny bit of tweaking -
the airbox kit is a lot of work- the box doesn’t really fit and no way to mount it-
you also have to run the accord MAF housing that’s in the kit which means you need a tune to adjust the MAF scaling-
get the stage one kit,get rid of the airbox resonator,open the inlet on the airbox to 4 inch and that’s about as loud as it’s gonna get for you
trust me I have a garage full of tried and failed parts !

 

Will going with stage 1 kit and doing what you recommend throw any codes?
Do you know if there's any vids around doing for doing this job? the resonator seems far back on the intake how can it be removed with the stage 1 kit ? wouldn't there be a longer pipe needed? or maybe im just not understanding correctly. do you have any pics or vids? just want to see what it looks like so I can copy that

Thank you sir very helpful, I will try out that route. honestly I don't need nothing to crazy the car is just sooooo quiet which I know is by design and average customer probably loves that - but I just want a little bit of sound at least

last questions I swear

 

Accord stage 1 works fine no cel-
takes a bit of tweaking to get it to fit right but it’s works
you NEED to get rid of the resonator on the airbox is keeps everything quiet
but after that you will be inhaling hot air- hence the duct from the l/f battery intake grille

 

just picked up the green filter and the PRL accord stage 1 intake tube to start. Give that a go for awhile.

 

You are running the stock airbox and stock panel filter (or K&N replacement I think). Do you think that square panel filter flows enough or could it benefit from more surface area?

 

I had a k/n and now I’m using a green filter- no difference-
the airflow through the MAF isn’t even close to being maxed out yet-going to a different type of filter wouldn’t do anything for power -

 

Ok guys a few days have past since the failed attempt on the aem intake. Since then I have testing a different solution.

I ordered an oem replacement air box lid from Acura for only $50 tax in CAD. Way cheaper than I thought it would be btw.

Long story short, I dremmeled out the MAF section from the air box lid. Since it’s a 3.125” tube, a filter connects to the tube perfectly and the other end connects to the oem accordion coupler is the exact same location and angle.

So far I have logged 200km at a wide range of throttle and speeds with NO check engine light. Previously the aem tripped the light within 20km. I’m still not saying this is THE solution, I’m just saying the results so far look promising.

Still get great whoosh noises as with the metal pipe. I think this time the computer is seeing acceptable readings from the maf sensor. Time will tell.

if this works I’ll replace the oem accordion coupler with a smooth 4 ply silicone coupler that is 3.25” and tappers down to 3”. I keep you guys posted on the progress.

 

👏 nice job-
you are right in that as long as the MAFsees and reads the same amount of air the cel won’t come on-
big negative about the open filter I have found is that the intake temps are way too hot because the air that goes through the radiator gets sucked in-if have seen as high as 140. Degrees in slow traffic-

 

thanks I’m still gonna look into how I direct fresher air to the filter. I’m not too worried about intake temps currently as the temperature is dropping here. In the summer I’ll re visit that aspect. For now I just won’t check the intake temps 😂

 

was trying to find a good image but the spectre intake filter you could use their tube attachment and setup a ramair and run it to somewhere pulling cold air.

 

Just have to run a duct from where the battery draws in cold air-
thats what I did and intake temps hover around ambient air temps most of the time

 

you should be more worried about how to lower the temp through the inter cooler than the intake. Yes, sucking in hot air is not good, but thinking about other temps downstream can become more important as the temps rise.
see
https://www.enginebasics.com/Advance...0Sprayers.html

 

agreed thats why the first mod on my aspec was the intercooler, then the k&n drop in n now ktuner. Reading threads n threads on heat sink also was a good guide lol

 

@whiteonred, kudos to you for having the interest and passion to experiment with this.

 

👍🏻 Thank you

 

What's up brother, does the stock cold air duct remain in place? You know the black plastic scoop thing that runs to the front, over the rad support.

 

that’s gets bypassed- you can leave it in its place because the resonator box is taken out and put on the shelf-so there’s gonna be a bit more whoosh noise-and
ive found that unless you are at highway speeds the hot air from the radiator makes its way into the air intake and the inlet temps are way high- like 30 plus degrees above ambient temps
- on my car with the duct that I made th intake temps never go more than 5-10 degrees above ambient even in standstill traffic