I have a 13 p31 and just don't know if this is normal and just the nature of these engines.Most times in park I can rev the car and it's an insanely nice rasp and amazing throttle response and sometimes when I do it the gas peddle is mushy and the car sounds very smooth and not as raspy and throttle response is very dull.

is this normal?

 

Happened to me a number of times. Sounds muffled, like 50% normal volume and eagerness to rev. Never figured it out. Curious as well.

 

ok I'm glad I'm not the only one.i have tried changing air meters and I'm now about to run stock air filters

what filters do you run?

 

Most people will agree that filters don't really gain any power. The benefit is from reusability. I run weistec filters which look the same as the aFe dry filters.

 

I had it when my filters were dirty occasionally I would rev in park for people that want to hear and the car would shoot the revs up really high and stick for a second all on its own. It is a weird thing. Like I would rev to 4-5k and then let off and rev a little lighter but RPM would shoot to redline and bounce once or twice up there.


EC V5 tune and RoW boxes+ AfE prodry

 

aFe Pro Dry S. Used lightly-oiled K&N and BMC as well. They all do the same thing.

Changed my MAFs over the winter. Made no real difference in regards to the subject of this thread (which I think is muffled sound while revving, not uncontrolled redline revving)

Still get it on occasion. I really don't know why.

 

Have noticed this on cold starts - most likely due to the richer mixture.

On cold start a 1.5k rev sounds ungodly, but once it's warm, you need some serious exhaust works to get it to snap the way it does when cold.

 

+1 Same. It is extremely weird.

 

We are beating the filter thing, just like we have with the engine oil thing to death. I have had K&N with no issues and some people have had MAF sensor issues from them. Some people use AFE, and some state that they are cheaply made. Some people swear by BMC. The difference felt is insignificant from strictly a filter type.

Revving at standstill vs. placing load is totally different acoustics.

 

Sometimes when I cold start the car it basically reacts like a warm start. Doesn't have that nasty bark followed by that loud V8 rumble. Happened this morning actually.

Most of the time it cold starts properly, though.

Maybe the root cause is also related to the topic of this thread?

 

Interesting - same exact thing happened to me this morning.

 

guys I'm not talking about cold starts lol I know how great it sounds on cold starts too but I ment after fully warmed up sometimes the car in park is very lazy and mushy on the revs when u jab the gas pedal and the engine is very smooth and no bark or rasp.

the revs also don't shoot up really fast and there is a huge throttle delay.t hen days later the throttle response is razor sharp and the car sounds like a race car

 

My car does that as well occasionally.
I usually just pop it into neutral and give it a rev again, then it's loud and eager again

 

my car is normal again today

 

my car only revs to about 4k when in P or N

 

Recently I've been having the issue where I step on the throttle and it kind of stays a wide open for a little longer then I expected.

 

I think I know exactly what OP means about this.

Sometimes the car feels meh, like "quiet" and not impressive.

other days the car feels much more "alive" and every light and push and rev is just loud and barks and pops and crackles everywhere.

This is of course taking into account that both times I am talking about I am driving the same and in the same mode (S+ all the time for me unless I am in M. Driving habits are always the same)

 

Any solution? Maybe its a tune that giving inconsistency? I am having same thing

 

Sometimes you feel like a nut, and sometimes you don't.

Seriously tho, I understand the curiosity but its definitely a non issue that could be weather related or a host of other things. Just stay away from revving your car in high school parking lots and you'll never be embarrassed lol

 

I noticed this too.. I rectified this by shifting to drive then I could rev to redline

 

That's by design.

 

also do you guys notice when driving in Comfort mode downshifts tend to be quiter then when in manual mode?

 

I revved like twenty times in a row in neutral. Does this hurt the car?

 

 

you are soo lame