Hello all, been a while since I've logged onto the forum, But I've had my TL-S (6MT) for about 2 years now, and for the most part has been a solid and reliable car considering the Mileage. Its now at 138,000 mi. and I'm needing to address a few issues. Could you all please point me in the right direction. Just to start, I've scoured the forums for these issues thouroughly and SEARCHED, So please don't flame me lol.

1. The first and main issue I've been trying to hunt down and address for the past 6 months to a year is this excessive road vibration while driving. It used to be much worse, and the car would veer and torque steer to the right very badly, but I've gotten an alignment a couple times, Brand new tires for the front, and rebalanced my tires, and finally, I replaced the Control Arm Compliance Bushings. The road vibration has improved slightly, but is definately noticeable at highway speeds of 70mph+, and can feel it in the steering wheel.

Could it possibly be my motor mounts causing the vibration? Ive noticed that my driver side mount has some slight tearing/cracking in the rubber, and the driver side I'm unsure of as it has a cap covering it.

2. The second and most recent issue I've encountered is a CEL code P0420, Catalytic Deficiancy Bank 1. Ive had a couple Bank 1&2 Lean codes (P3071 & P3072 I believe) come on once or twice in the winter the 2 years I've owned the car, but they always went away on their own and I just figured the O2 sensor was just being lazy or was a slight misreading. But this P0420 Code I'm a little concerned about. I cleared the code with a code scanner, and drove the car for about 3 days and Filled up with Shell Premium 93 Octane fuel, and Today the same code came back.

So, What are my chances that my Bank 1 Cat is actually bad, or is it possibly my O2 Sensor is finally going out? I don't want to blindly throw money at the car and spend more $$ fixing the issue.

BTW, if my cat truly is bad, I've been considering RV6 HFPC's, and was wondering if they would keep the CEL from coming on and allowing me to pass emissions with the O2 Sensors installed.

Thanks in advance for the support and advice guys

 

1. my bet would be out of round wheels, seems quite common on tls waffles.
the drivers side one is a transmission mount. you have 3 motor mounts(front, rear ,and passenger side) if you never changed it Im sure they are bad by 138k miles

2. might be the sensors going bad. I dont think cats really go bad? If they do, I guess you can go for the rv6 hfpc, but they will not come with new sensors. and yes they will pass the sniffer during smog check. Will not pass visual, but thats a minor thing they will usually look the other way or as they say, money talks. At least thats how it works here in socal, not sure about your area

 

Ok, I will look into the mounts for sure. I've read that they usually wear out at lower mileages, so maybe thats contributing to the road vibration, it also has some slight vibration at idle in the cabin throught the steering wheel.

As far as the wheels, I don't believe they are bent, but when my car is up in the air on a lift tomorrow, I will inspect them further.

I guess your right, I may just end up buying the O2 sensors first, and if that fails, opt for the HFPC's. I'm going to smoke test tomorrow too and see if there might be a vacuum leak somewhere causing the code to trigger.

 

I find it hard to see how motor mounts are contributing to driving vibrations.
Why do you think the wheels aren't out of round? You cannot tell by just looking at it. Only way to check is to have the wheels spinning either on a balancing machine, or put the car in drive while on a lift/jack stands. Just let the brakes off and the natural speed of being in drive should be fast enough. Look carefully at the wheels, most noticeably the inner barrel as that is much weaker than the outer lip.
Reason I say this is that I've seen a lot of posts about vibrations and this is usually the cause. I've also seen a lot of bent tls wheels personally.
In any case, good luck with whatever you find.

 

Hey Thanks again @paperboy42190. I have thought of that being a reason in the past when I was replacing tires, and control arm bushings. I have looked at them closely while up on a lift for any bends. I guess it is possible for a slight bend to be there that i can't see with my naked eye. I do know that they are pretty lightweight alloy wheels so it very well could be possible. I may try roadforcing my tires too to see if they are out of whack.

But more importantly at this point is trying to resolve my P0420 code as I have to renew emissions in a couple months

 

Oh and to add, does anybody recommend a cheaper aftermarket alternative to OEM O2 Sensors? I have been looking at RockAuto, and Bosche seems to be a reputable brand in my past experience with my BMW's, but I have read mixed reviews on these forums. And Does any know if the Type-S has a 3 wire O2 Sensor Setup, or 4 Wire? I'll probably just end up looking when I have the car up in the air, just wanting to do some HW.

 

Is there more than 1 code or only the one? The code you mentioned I think is bank 1 catalyst has low efficiency. It could be the catalytic converter or maybe like you said a misreading oxygen sensor.. Does the car smell a little bit rich at all? If it smells a little bit like rich fuel exhaust, then you might not have an oxygen sensor. The problem could truly be the catalytic converter. The catalyst burns off residual fumes from the engine so it burns cleaner. If it smells a little bit rich then it may not be working up to par. If it doesn't smell rich whatsoever, then maybe the oxygen sensor is not working so great. but I think there is another code for an oxygen sensor. So, if this is the only code, then it may not be an oxygen sensor that is at fault.. So, how many miles are on your car? And Have you ever replaced any oxygen sensors or catalytic converters in the past?

 

Hello all, Just an update on my issue.

I've cleared the P0420 code for the 2nd time, and haven't had enough drive cycles this past week to really test to see if the code has come back (only drove car twice this week). But to answer your question, no, the cabin or exhaust of the car does not smell rich whatsoever, from what I can tell at least. And yes, I have had an O2 code (P0171, P0174, but NOT both at the same time) that intermittently came on and went away on its own once last year in the winter time. I've owned the car 2 years, bought it with 110K on it and the car currently has 138,XXX miles (drive everywhere), and the cats and O2's are all original from what I can tell.

I did however have my mechanic friend check my car out, we smoke tested my intake system for any vacuum leaks, and everything is solid there, no leaks at all.

For my vibration issue, My suspension components seem to be holding up decent enough, my Control arm bushings are brand new, I replaced them in the spring. We checked my wheels, none are bent, and we road forced and balanced my tires. one tire had excessive road force due to a manufacturing defect imperfection in the mass weight of the inside of the tire, so we offest and balanced it out the best we could. It has helped my vibration a bit, but it is still there a bit.

We also checked my Motor Mounts, and like many have posted, They seem to be on their way out. I have some excessive engine flex when engaging the clutch and giving throttle. The mounts have some minor visible tearing on the rubber bushings. I have a feeling the mounts are causing the rest of my vibration issues.

So, I will continue to drive and check to see if P0420 comes back, (hopefully it doesnt) and will be looking into replacing my engine mounts in the near future.

Has anyone had any positive experience with Innovative Mounts seen on Heeltoeauto.com, or are OEM the way to go?

thanks again all.

 

The most common issue that I see causing steering wheel vibration at 40mph+ is bad CV axles. If it is an axle, generally you (or an experienced person) can easily determine which side the vibration comes from the most while driving. If you find out it is the CV axle causing the shimmy, I recommend NOT using aftermarket axles. That's because they generally do the exact same thing OR they may cause drivetrain related issues due to improper length after being reman'd or rebuilt. Better off using dealer or used axles.

As for the P0420 code, though it COULD be a faulty O2 sensor, it's not very likely. You mentioned that the engine was running lean on both banks previously (believe the codes are actually p0171 and p0174) and running too lean could have physically damaged the cat due to increased temps. Again, I'd recommend installing a dealer only or used catalytic converter rather than a cheap ass aftermarket one.

 

Well, when we were under the car checking components, my passenger side cv joint boot has some minor surface cracking on the surface, however, there seems to be no leakage or excessive play withe suspension somponenets

As far as the O2 codes, when I first got my care in January 2013, I have P0174 come on after I bought the car, but it went away on its own within the next day. Same with P0171, Happened latst winder and went away by the next drive cycle. But P0420, has come on twice now in the last 2 weeks after resetting the code. If my cats do turn out to be the culprit, Do the Rv6 HPFC's give OEM a good run for their money as well as some nice littel gains?

And on the Motor Mounts, after doing some reading/research, The Innovative Mounts are sitffer do to the Urathane, and could possibly be counter intuitive if I'm trying to smoothen out my ride and get rid of this vibration issue once and for all! Any thoughts or experiences from any of therse products?

Thanks