leisinjp

Hey guys,
Long story short I owned a 2008 ISF two years ago and installed the ISS DES exhaust on it with the help of a buddy who works for Toyota (he knows his stuff). It was perfect, sounded deeper than stock but had absolutely no drone and wasn't annoyingly loud. Sadly I sold the car. I recently purchased another 2008 ISF about 3 months ago. My buddy moved so I took it to a performance shop around where I live and had another ISS DES exhaust installed thinking that it would be exactly like what I had before. The results were not what I expected. The car is all around louder, has a drone between 1500-2000 RPM"s, you can smell the exhaust more, and I can feel more vibration through the pedal when I am accelerating.

So far I have taken the car to a regular oil change shop, the Lexus Dealership, and a performance exhaust shop. Regular oil shop said it looked good, lexus dealership said it looked good, the performance exhaust shop recommended replacing the mufflers. I also spoke with a gentleman from ISS directly, he has been great help and willing to help however he can. Issue is that I live 14 hours away from their HQ therefore they can't look at the car themselves.

I will list everything I know about the car and if any of you guys have any recommendations I would appreciate it.

- Previous owner said that dealership notice two small cracks around the primary cats, so they welded them.
- Primary cats are still on the car
- Previous owner removed the secondary cats and straight piped the mufflers (I removed that setup as soon as I got in my ISS exhaust)
- Purchased the ISS DES exhaust used from a performance shop
- Had the exhaust installed by performance shop
- Had three places look at the exhaust, gaskets, and so on with all of them saying it looks fine

This is getting pretty frustrating as I can't think of what else could be causing the exhaust to be so much louder and drone compared to the first one.
I did read something about the exhaust manifold flange seperating away from the heads. I'm going to have this looked at as soon as I can figure out a way to see them.

5280ISF

Hmm, did ISS change their mufflers / design of the system? You could put it on some ramps/ jack stands and make sure all bolts are torqued to spec. I know I had to do some small adjustments to the pipes on my Borla after I installed it. You could also check to make sure no pipes are touching the body/heat shields anywhere. Make sure heat sheilds are snugged down and not vibrating? May need to think about replacing those factory manifolds, my 2012 had a flange broken when I replaced them last week with PPE headers. My car has 26K miles... Hard to say though if three shops say everything is as it should be.

Good luck and report back on what the issue was.

leisinjp

5280ISF,
When I spoke with ISS they said they made some changes to the system but that it all had to do with making it better quality and nothing that would change the sound of it. I've done most of that, looking under the car, checking if anything is rubbing. It all looks good.

Has Lexus came out with anything to help people with this flange breaking prematurely? I really don't want to spend $3k on the car just for headers to fix a problem that shouldn't been there.

5280ISF

Sounds like you have checked everything.. I have heard some people have had their factory manifolds replaced under warranty. May be worth a call to Lexus corporate to discuss the cracking problems you've experienced. The factory pieces are weak and restrictive, I would ditch them if I were you.

Me and some friends of mine - (other local ISF owners) installed my headers in 3.5 hours. That may be an option if you go that route. Greatly reduces install labor.

other option is to plan a road trip to ISS, maybe they have an older version of their system they could swap out for you?

FFM

Real question is, ISS is still selling ISF exhausts?! I thought that was a thing of the past.

leisinjp

Yea FFM, I love the look of the actual round dual exhaust tips. I'm not a fan at all of the oval stock tips.

5280ISF, I've been talking to a guy who might be able to help me with install but either way the headers themselves are still $1,800! I just hate spending money on something that the company made a mistake on. They clearly made the manifold weak since so many other ISF owners have had this issue. I will give Lexus a call and see what they say. I would love to get headers but right now I'm just being bitter about not being able to figure out the drone and issue after putting in so much time and research.

msgs350

iTrader: (2)

I don't think Lexus will help you if you have an aftermarket exhaust on your car. If your OEM manifolds have failed within the warranty period, sure I can see them looking into it but once you tell them about the aftermarket exhaust, you're on your own.

MileHIFcar

Here ya go the PPE's are $1500..........unless your dead set on getting Sikky V2 which are $1800 that will save you $300!?

http://www.rr-racing.com/RR-Racing-T...ppe950001s.htm

Tom2769

iTrader: (3)

Here are a few threads that address drone-reduction options for the ISS DES:

​​​​​​https://www.clublexus.com/forums/is-...s-results.html

This one is primarily about the Borla system, but read all the way thru the thread - there are a couple of us with the ISS DES that did this also with good results:

​​​​​​https://www.clublexus.com/forums/is-...-20-bucks.html

leisinjp

Yea that's what I'm afraid of. Literally two months ago I had the stock exhaust on there so I missed out on that one. What is the standard warranty on the ISF? I'm assuming since I'm at 112,000 miles I would be over the warranty.

leisinjp

Thanks man, I will look into it. I definitely want to keep the exhaust on the car. I just need to figure out how to reduce the noise.

Thanks for adding the link. I will look into it. Either way, it still sucks paying $1500-$1800 for something that Lexus screwed up on. I'm just being bitter haha.

MileHIFcar

^^^^^^^I hear ya! Sucks for sure and it definitely shouldn't be an issue but for whatever reason the part is failing way to often and it shouldn't be for the caliber of car the ISF is and what it meant for the Lexus brand IMO.....

msgs350

iTrader: (2)

The Lexus factory power train warranty is 72 months or 70k miles, whichever occurs first ( http://www.lexus.com/warranty ).
Do you have an extended warranty? Would it be worth it for you to put the stock exhaust back on and take it in, if you have an extended warranty?

leisinjp

I do have the stock exhaust but sadly I'm well past the factory power train warranty. I'm at 112,000 miles.