Yea I'm out
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Joined: Nov 2013
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From: Central Florida
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Joined: Dec 2009
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From: Framingham Ma,
Hey Mike, Sorry to hear that you're going to go in a different direction, can't say I blame you though. Wish you nothing but the best in whatever vehicle you end up with. Keep us posted, and if you somehow manage to turn back to Infiniti we'll be here 
Sorry to hear about your modding misfortune.
Don't the V8 S4s have carbon buildup issues due to the DI? I don't think a high mileage, high performance, forced induction, German car that has been thrashed on by who-knows-how-many-owners is going to offer great reliability.
Why not just take off the headers and ride out the G for a bit
Don't the V8 S4s have carbon buildup issues due to the DI? I don't think a high mileage, high performance, forced induction, German car that has been thrashed on by who-knows-how-many-owners is going to offer great reliability.
Why not just take off the headers and ride out the G for a bit
Personally if you're worried about funds and potential headaches the last thing I would be looking at is anything German with some miles on it. You're going for the doubly whammy IMO. IF you're sold on German I'd look at an A4 (common parts shared with Volkswagen) and it is tunable.
I'd consider a Pontiac G8. Quite reliable, have aged well and can be a blast to drive.... Doesn't hurt it's 4 doors, roomy (opinion) and can get one under 100k miles for $15k or so.
A 7+ year old Australian G8 from a defunct car company
If you have a $15,000 budget (or there about) a couple year old Accord or Mazda 6 with low mileage would be a far more reliable and practical choice.
If you have a $15,000 budget (or there about) a couple year old Accord or Mazda 6 with low mileage would be a far more reliable and practical choice.
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Joined: Apr 2014
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I'd stay away from BMW. Aftermarket parts are super expensive and reliability is poor. I looked into 335Xi before I bought the G. Stock vs Stock the 335Xi is faster and handles better. Interior I like the G more, exterior I liked the G a little more. The Audi is a better car IMO than the 335xi. I have a buddy at work that has a beautifully modified 2012 S4 and it's reliable, sounds awesome, interior is awesome, exterior is just as nice as the G IMO. It comes supercharged from the factory and tuning isn't that expensive. Mods aren't that bad either, about the same as the G price wise. I hope you find a nice S4 and buy it.
In terms of reliability, there are three things, HPFP, injectors, and turbo wastegate. The first two can be replaced in a garage, the turbos replacement is a much larger job, but at this point you'd be upgrading to larger ones.
I've also been looking at ditching my G37, I have some serious buyers remorse. I find it boring...
I've been looking at E60 535i m sport....just have not taken the plunge yet.
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Joined: Dec 2015
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Do I have this correct: You put in an aftermarket cat, got a check engine light (after many, many months), and now want to sell the car?
I think you may be giving up too soon...
Why not put back in the factory cats and see if the code comes back? There is a reason the factory cats may not be "high flow" but hold more oxygen for a slower switching of the rear o2, which = high catalyst efficiency.
A good shop would have a look at the post cat O2 to see the voltage level, frequency of cycling and have a look at the mode $06 data for catalyst ratio of switching.
On a different note, the electric water pump on the 335 is also a known weak spot. The pump is very expensive and about 6-10 hours labor: N54 water pump failure.
I think you may be giving up too soon...
Why not put back in the factory cats and see if the code comes back? There is a reason the factory cats may not be "high flow" but hold more oxygen for a slower switching of the rear o2, which = high catalyst efficiency.
A good shop would have a look at the post cat O2 to see the voltage level, frequency of cycling and have a look at the mode $06 data for catalyst ratio of switching.
On a different note, the electric water pump on the 335 is also a known weak spot. The pump is very expensive and about 6-10 hours labor: N54 water pump failure.
Mike I just had an epiphany. You had Z1 cats before and no issue. You installed headers and had issues. Specifically P0420/P0430 which still exist plus some knock detection. I have a theory that it's due to the fact that the Z1 HFC don't have the 02 bungs spaced away from the exhaust current. Everything was OK with stock headers, but once you opened those up you increased the flow more and that's why you're getting those codes. I have FI RHFC on my car and the Stillen headers and no codes at all. I believe it has to do with their design as the FI HFC's are spaced away from the exhaust current quite a bit. You could try to install 1 or 2 spark plug non-foulers to space the O2 sensors away from the exhaust current to see if that fixes the issue.
Mike I just had an epiphany. You had Z1 cats before and no issue. You installed headers and had issues. Specifically P0420/P0430 which still exist plus some knock detection. I have a theory that it's due to the fact that the Z1 HFC don't have the 02 bungs spaced away from the exhaust current. Everything was OK with stock headers, but once you opened those up you increased the flow more and that's why you're getting those codes. I have FI RHFC on my car and the Stillen headers and no codes at all. I believe it has to do with their design as the FI HFC's are spaced away from the exhaust current quite a bit. You could try to install 1 or 2 spark plug non-foulers to space the O2 sensors away from the exhaust current to see if that fixes the issue.
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