LOUD KNOCK during cold start

[Flat_4_Life]

Hey everyone,
New here to the forum. I've had my 2015 FRS since October now and I've been paranoid about every little smell, noise and feeling as I'm sure most of us are with new cars lol. I've experienced all the ticks and even crickets for a few days but on my way to work in the morning i fired my car up and by the time i went outside again the car was at normal running temp and idling around 750RPM and heard a very loud strange knock which scares the crap out of me. i have a appointment to get my cars first service done on Thursday and i let them know about this noise but the problem is i haven't heard it since but luckily i recorded the noise with my phone. the noises i hear from this engine make me sweat bullets and make me afraid to enjoy the car the way we are supposed to. anyway if any of you can help me find a way to upload the recording i took on my phone i would love for you guy to hear it for yourselves it is a audio recording not a video and i cant attach it.

[Tcoat]

If it went away then don't worry about it. Even the dealer won't be able to do a thing if it isn't doing it. These cars make some weird ass noises and it does not always mean there is a problem.

[Flat_4_Life]

Originally Posted by Tcoat

If it went away then don't worry about it. Even the dealer won't be able to do a thing if it isn't doing it. These cars make some weird ass noises and it does not always mean there is a problem.

I just can't help but feel like one day it will just grenade on me. Just forked out some cash for tires and rims and a openflash tablet last thing I need is major engine issues

[Bergen23]

Originally Posted by Flat_4_Life

I just can't help but feel like one day it will just grenade on me. Just forked out some cash for tires and rims and a openflash tablet last thing I need is major engine issues

Well if you've flashed a ROM, say bye to your warranty

[Flat_4_Life]

Originally Posted by Bergen23

Well if you've flashed a ROM, say bye to your warranty

Haven't even got it in the mail yet and that's not even the case with openflash. You can flash your ECU back to stock in the dealer parking lot in five minutes and they won't even be able to tell. All it will look like to them if they check is the battery was unplugged

[steve99]

Originally Posted by Bergen23

Well if you've flashed a ROM, say bye to your warranty

Errr no,

just flash it back to stock, no problem

please dont say flash counter
your just scaring people unnecesarily

[Bergen23]

Originally Posted by Flat_4_Life

Haven't even got it in the mail yet and that's not even the case with openflash. You can flash your ECU back to stock in the dealer parking lot in five minutes and they won't even be able to tell. All it will look like to them if they check is the battery was unplugged

That won't help if your engine grenades and gets towed to the dealership unless you carry it everywhere with you

[BRZnut]

would have to agree with Tcoat..these cars make a lot of noise esp when first started. Driving for 40 years and have never heard anything like it (my first boxer though).


Let us know what the dealer says.

[Tcoat]

I think what a lot of people are hear and interpreting as "knock" is the change over from port injection to direct injection. Having spent many years with old carbourated V8s I know I will never get used to the noises injected systems make (if my 440 made those noises it meant something very bad was going on).
So many are very sensitive to sounds from reading the bad things that happened to a small minority that every change seems to be something wrong. I am not totally immune to this paranoia as just the other day I noticed a slight ticking sound and my mouth went dry and pulse shot up to probably very dangerous levels. I turned off the radio and listened and sure enough there was a very regular click. It wasn't loud but was there. Got out and opened the hood and could not hear it. Goat back in and there it was. Turned off the heater blower and it was gone! Turns out that since it got warmer I turned the fan from 3 to one and at the low setting the heater makes a very faint click.
After all my "don't worry it is only a few with problems" comments I was more afraid of having to come on here and say I had an issue then I was of actually having one!

[mav1178]

Originally Posted by Flat_4_Life

I just can't help but feel like one day it will just grenade on me. Just forked out some cash for tires and rims and a openflash tablet last thing I need is major engine issues

... so you're afraid of engine issues, yet you have no problem modding the engine?

It's just an honest statement: if you can't afford to replace the engine, don't mod it if you have abnormal sounds or symptoms.

As for whether the symptoms can be duplicated or not, just document it and have the dealer inspect/document it. The last thing you want is to not have a paper trail of known issues, the more you have it in writing the easier your life will be later on.

-alex

[Koa]

Originally Posted by Bergen23

Well if you've flashed a ROM, say bye to your warranty

srsly berg they can't track rom changes using the method OFT writes with..

If he's suspecting having engine troubles and it grenades without the tablet in the car.. well that's his fault

[Cope52]

How come I only have this knocking sound after startup since the dealer handed the car back to me for a power windows failure?

[Tcoat]

Originally Posted by Cope52

How come I only have this knocking sound after startup since the dealer handed the car back to me for a power windows failure?

They may have disconnected the battery to do the work and the ECU has to relearn. Car can knock for a bit after that but it should be gone quickly.
If it has been a while already then I don't have a clue and never mind the previous statement.

[Bergen23]

Originally Posted by Koa

srsly berg they can't track rom changes using the method OFT writes with..

If he's suspecting having engine troubles and it grenades without the tablet in the car.. well that's his fault

Shoulda elaborated more. Just pointing it out. I always have the tablet with me now, just in case. Be super shitty to be denied warranty for a minor thing such as a flashed rom