AEM 21-821DS Cold Air Intake System, 1 Pack

No missing parts. Moderate install, (took about 2 hours). Looks and sounds great!!!

Great Cold Air Intake, But Installation is a Nightmare – Read This Before You Buy!This review is long and detailed because AEM completely dropped the ball on the installation instructions. Aside from one other review, there’s almost no guidance on how to install this properly, and it’s nowhere near as easy as AEM claims.The Good – Why I Chose This IntakeFirst, let’s talk about what makes this AEM Cold Air Intake (CAI) awesome:✅ Looks great – Clean, aggressive design without excessive chrome.✅ Keeps the engine bay organized – Unlike some intakes that route tubing around the crash bar, radiator, or wheel wells, this setup keeps everything in a smarter location.✅ Solid performance gain – Expect about 6-12 HP to the wheels over the stock intake system.✅ No unnecessary tubing in bad locations – Unlike some CAIs, this one doesn’t require placing air intakes in awkward or questionable areas.For those considering alternatives, Stillen makes a similar CAI (Gen 2) for about $600, which is $200 more than this one. It may or may not be easier to install, but the biggest challenge with both is getting the airboxes to fit in the tight space with NO wiggle room.The Bad – Installation is Extremely DifficultThis install was grueling, mainly because of the poorly designed instructions and tight fitment issues. Here’s what you need to know:1. Prepping the Airboxes (IMPORTANT!)• The airboxes are NOT identical – there’s a passenger-side and driver-side box, so don’t mix them up.• Threaded holes were painted over – I couldn’t even assemble the boxes because the paint blocked the threads. Luckily, I had a tap and die set to clean them out—otherwise, I’d have been stuck.• The kit comes with a rubber seal in one long piece, and you have to cut it to size. I assembled the boxes first, applied the rubber seals where shown in the instructions, then disassembled them again, leaving the bottom part of the seals in place. You’ll need to reattach the top seals when installing the upper housing.2. How to Actually Install This Intake (Correct Order)The instructions suggest installing the intake as a single piece, but this is impossible. The only way to do it is piece by piece:1️⃣ Install the bottom half of the airbox first – This goes where the stock airbox was. It’s the only way this will fit.2️⃣ Driver-side only: You will need to adjust the fuse box bracket to make it fit alongside the AEM airbox.• I personally had to bend the bracket slightly so that it could sit behind the airbox instead of interfering with the installation.3️⃣ Attach the filter to the intake tube, tighten it, and slide the coupler on the other end. Leave everything loose for final adjustments.4️⃣ Position the air intake tube and filter inside the bottom airbox housing.5️⃣ Apply the rubber seals as you bring the top airbox housing down over the filter and tubing. This part is tricky but must be done during assembly.6️⃣ Secure the airbox housing with the correct screws:• Use pan-head screws for the upper airbox cover.• Use hex-bolt screws for the bottom portion. (There are 4 hex bolts and 8 pan-head screws, so you can’t really mix them up.)7️⃣ Install the mass airflow (MAF) sensors:• DO THIS SEPARATELY. Remove the sensors from the stock intake before starting the install.• Disconnect the wire harness, install the sensors into the AEM intake tubes, and only reconnect the wire harness at the very end. This prevents damage to the fragile MAF sensors.8️⃣ Adjust and tighten all connections:• Straighten out the couplings at the intake manifold and tighten them up.9️⃣ Reinstall the PCV breather hose:• This was a pain because the factory hose is difficult to reroute to the new intake tubes.• I ended up ordering an aftermarket set of silicone PCV breather hoses from Z1 Motorsports – they’re more flexible and have pre-bends, making installation much easier.🔟 Reconnect the wire harness to the mass airflow sensors.1️⃣1️⃣ Reconnect the negative battery terminal, double-check all connections, and start the car.What to Expect After Installation• Your Check Engine Light (CEL) may come on because the ECU (engine control unit) has to recalibrate for the new intakes.• It may take 15 minutes of idle time or 3-4 drive cycles for the ECU to adjust.• If the CEL doesn’t go away, there may be an issue with the MAF sensors, but don’t panic right away—give it time to relearn the air intake changes.Final ThoughtsOnce installed, this AEM CAI is fantastic—but getting there is a challenge. If AEM had spent more time on their instructions, this would be a 5-star product. Because of the frustrating install, I’m giving it:⭐ 4/5 stars – Excellent performance, terrible installation experience.Hopefully, this helps anyone struggling with the install like I was. AEM really needs to step up their game on the instructions. If you’re ready for a challenge, this is an awesome intake—but if you’re not mechanically inclined, be prepared for some frustration!

First off the power is noticeable but sound of the intake is not noticeable if you have an aftermarket exhaust. Still worth it and I will be enjoying the car more now. So for the bad, the install is a pain. The L shape adapters are plastic and one of mine broke during the install. The metal cover barely fits in the whole area. Once you get it in it’s fine and fits fine but is a pain to get in.

easy to install comes with step by step instructions, can’t go wrong with AEM and the fit and finish is great.

Some of the instructions are impossible to follow, and I broke a part putting it together but they was user error, other then that it’s very good quality and makes my engine bay look a lot cleaner

After trying to put this together the way the instructions in the box say, I gave up after 30 minutes of trying to clear the entire assembly under the hood at once. I figured out what they were TRYING to accomplish and simply put the bottom of the airboxes in first , the maf tube to the tb and then put the filters on and then finally , the top of the airboxes.Once I did it MY way, the thing went together without a hitch and would only take about 30 minutes total.So, great product, looks great, sound great, dynos 10whp per my dyno run, just don't follow their directions all the way!

Instructions said to build the intakes and then install them as a single piece I found it easier to install it piece by piece into the car

Good quality, for the price its hard to beat. Install is moderate in difficulty but once installed it looks nice and clean!