So I've noticed a few things that concern me with my 2015 GSR and I want to make sure this is normal behavior. This is my first turbo car.

1: When I let off the gas, I'm noticing that sometimes the car does not decelerate. Instead, speed will be maintained. I also notice the real time mpg bar doesn't max out like it does other times when i let off the gas. I've had this occur in any gear but randomly. I would say about 80% of the time, when i let off the gas, the car decelerates as normal.

2: the passenger side airbag light on the dash flickers randomly when no one is sitting in the passenger seat. Not sure how to troubleshoot this and taking it do the dealer seems fruitless as I can't consistently figure out the cause.

3: I installed the K&N Typhoon intake as I liked the fact it had a heat shield and used the stock funnel to blow cold air on the filter. Anywho, I noticed the increased volume with the blow off valve but when i hit boost, the waste gate is extremely loud. I can't remember how loud it was before the intake but I just want to make sure this is normal as well. I did read through searching that the factory internal wastegate is designed to bleed off boost all the way until redline instead of just at redline or when peak boost is reached.

4: Lastly, i'm concerned about the power level of the car. It just doesn't feel very fast. When driving spirited lets say from 3k in 2nd and I floor it, I feel an initial pull but the power really dies off after 5k until redline. I'm coming from a 2011 Civic Si which was not fast or powerful, but seemed to feel better than the Evo.

Thanks for any help in advance.

 

I wouldn't run an intake without a tune.

 

The intake will cause engine damage as the oiled filter does not filter air like the stock air box, heat soak and other issues since you don't have a tune for the new air fuel mix.

Take that off right now.

if you wanted a fast car is straight line why didn't you buy a Mustang GT with over 400 horsepower and then put a Roush supercharger on it gets 620 horsepower for under $45,000

 

1 Never an issue with my car. Maybe someone else can chime in.

2 Never noticed. Have to check next time I drive.

3 Turbo spooling, hard pipe intakes are loud. Open element... even louder. You should look into a tune.

4 Normal. Run a search is you want to read up on it. Again... A tune will fix this and make it pull all the way to redline.

 

You need to also FLOOR IT. Not half pedal, not granny touching it, these cars have horrible 'feel' through the pedal. So PUNCH IT foot to the floor and then you'll feel the power.

Take the intake off ASAP. And research before you modify.

 

1) Normal; emission control.

2) Normal, mine does this also.

3) Not sure, but I've noticed a louder blow off valve and a woosh sound when the turbo makes pressure even with just a drop in filter, so I'd expect everything to be louder.

4) Yea, power dies off in the higher rpms. The stock tune is very conservative. It's said that even with just a tune, a stock car will make 30-40 more hp.

Having your intake on without a tune is fine.

 

1. This can really depend on your RPM and what type of incline you are on. Low RPM or going down an incline... you might not notice much engine breaking effect. High RPM or going up-hile... the engine breaking effect will be exaggerated. It might take it a bit, but your MPG meter (lol) should eventually peg at max, as the the car will stop injecting fuel during these periods. Unfortunately, that MPG meter doesn't respond right away, and even a wideband will take a few seconds to show full lean. IMHO what you described seems normal to me.

2. I have ~115k on mine (08 gsr) and never noticed that. Might be worth making sure the airbag harness (I assume there is a junction under the seat somewhere) is tight. Disconnect the battery first. I believe it's weight / pressure based so it shouldn't be doing this if the seat is empty. If there is like a backpack on there or something it's completely normal.

3. The factory vlow off valve is MUCH louder with a hard piped / cone intake than with a stock intake. Stock is barely noticeable. It becomes a bit more noticeable with a drop in panel filter, and is very noticeable with a full intake. I guess you could also be hearing the bleed off from the waste gate activation line if that's what you meant regarding the wastegate. The wastegate itself is in the exhaust stream and your intake shouldn't change the volume of the WG itself. The turbo compressor is connected to the waste gate which applies pressure to the waste gate (which is sprung). When the air pressure overcomes the spring pressure, the WG opens. The stock boost control system uses two solenoids that are on a tee off of that line that connects the compressor and WG. The ECU opens those solenoids to bleed off pressure from that line to better control boost. I don't know if you can hear that air re-entering the system; however, it does enter upstream of the MAF sensor on the intake (so it's metered air). I never noticed it... but it could be something you are hearing. You shouldn't be hearing the waste gate itself (the exhaust portion in an open waste gate is way louder than any air). You probably do hear the turbo spooling and sucking air through the intake (there is a huge difference in intake sound with that sort of intake... it's lovely).

4. Get a tune.... especially with the intake... preferably after getting a test pipe or HFC and cat back system if you are going to go that route. Also get a 3-port for boost control (super cheap and you want this before you get a tune).

 

1- higher rpm will solve this, down shift if your rpm is too low

2- I noticed the weight sensor in the seat is very sensitive. My backpack trips it. So do bumps.

3- remove it, as others have explained

4- get the car tuned and it'll wake up. If there are no tuners in your area, just buy a cobb access port. Ots tunes are better than stock. I noticed a large difference with just an hks panel filter and an access port.

 

I noticed the decel your talking about back when I had my 08 gsr. I would let off the pedal and would maintain same speed. Always thought that was weird.. I want to say the 2010 or 2012 models had that problem fixed... But it might just be the way they are!

As for the lack if power, seems to be normal. You would expect it to have a little more "umph" but like everyone is saying, get a tune on it.

With the intake on there I would advise atleast investing in a cobb accessport v3. They have tons of maps for just minor bolt ons and would be a lot safer route then just having the intake on it with factory tune. Deff look into that.

Get the hard pipes, bov, exhaust and maybe a boost controller and schedule a professional tune and ull love it!

Good luck

 

1/2: you are fine....
3: 99% sure you aren't hearing the WG...if you are then you have an issue and they are pretty solid built so on a new car the chance of it failing is almost non existent. Just alot of air moving in..enjoy the sound lol...oh and with the K&N you DONT need a tune you arent hurting anything...it keeps the oem size maf so you are fine....but getting at tune will completely change the car for the better
4: you gotta think how much heavier this car is than alot of other cars in the class or those below it...I have a ton of friends that when she was stock said it felt slower than their cars when they drove it but I would walk on them with no issues...but yes the oem setup is set to taper boost/power as soon as you hit peak so since you are stock you hit 21 and instantly start dropping boost to about 18 if I remember correctly. Like others have said get a Cobb AP it will change your car...or if you can drop a little bit more money either get a cobb and a protune or just get a protune and not get the AP at all...you will still taper but you will taper from like 28psi to 22 ish so you will have alot more power...could swap WG to hold boost to redline but I would talk to whoever tunes your car if you do that....good luck!

 

2. My light also blinks, probably normal.

3. K&N Typhoon Intake is not going to hurt your car without a tune. Very much safe to run. It uses the stock MAF housing so you don't need to worry as you would with say, the AMS intake. You're now just hearing all the beautiful noises that were dampened by the stock air box.

4. As others have said, a tune WILL liven the car up. Stock form, these cars aren't that fast. They do respond extremely well to mods and tunes though. Even stock, they're much faster than your 2011 Si

 

Thanks guys.

Yeah, I've already done alot of research and know that the K&N Typhoon doesn't change the MAF intake size (stock 3") vs units like the Cobba and AMS which go to 3.5" (which is why you require a tune). I'm not new to cars, just turbo cars. So a tune is not required (however I did purchase a Cobb AP and have loaded the Stage 1 map adjusted for the K&N intake so I'm good there).

So regarding the sound, let me try to give an example short of me recording it.

Let's say i'm at 2500 rpms. 2nd gear. I begin to ease into the gas, I immediately begin to hear a sound similar to what the BOV makes when you let off the gas. Not quite a whistle but like someone is blowing air through a small straw, very fast.

Then as I get to full throttle and the rpms are around 3500, I hear a second, much louder sound of air separate from the above noise coming from the right front (from the perspective of me the driver). It's very loud and I guess you guys are right, if it was the actual wastegate noise, it'd be different since that is exhaust (I've never heard a a divorced to atmosphere downpipe, I only assumed it was the wastegate).

I might have to just take a video. Unfortunately Evo's are a rare sight around here so I don't have anyone local to bounce this stuff off of.

Thanks again!

 

EVO's have all kinds of odd noises in general. It may very well be normal, but if you changed your intake, that could account for the noises you are hearing as things like the wastegate / blow off valve will become much more noticeable.

 

I wonder if I have a boost leak. I ordered a tester (2.5") to attach to the UICP downstream from the turbo outlet into the Intercooler. I might get a second coupler from Lowes that will fit on the intake side of the turbo too. That's the only other thing I think it could be.

 

1. That's normal as it's for emmisons, the throttle body stays a bit to reduce pressure in the intake manifold and burn excess fuel

2. That is also normal, both my evos have done it

3. That is also normal, the bov gets louder because an after market intake won't silence the bov sound as the stock intake is made too

4. Stocks evos are very and I mean very slow, the stock tune sucks and only makes about 240 so yeah they are slow lol once you tune it you will see the difference