CEL P0420; Steps for Diagnosis

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I'm new to the Corolla Forum. I currently am a member of the Taco forum and it provides amazing useful information. So thanks in advance to all those that manage this forum and to those that contribute so we can all learn and save money.

Wife's Corolla:
2002 CE auto 86K miles

The CEL came on a few weeks ago. The dreaded P0420. I decided to start at the front of this potential problem and clean the MAF sensor. Light came back on so I'm assuming the signal there for air:fuel is fine.

My next step will be to compare the voltage of the upstream and downstream O2 sensors. I'm assuming this will check out. If there was an O2 sensor problem then there would be a CEL code for that, right?

I'm finding it hard to believe that an O2 sensor or catalytic converter has gone bad in 86K miles. What do you think?

What would be the next step for diagnosis if the O2 sensors and cat converter check out? Exhaust leaks? What else?

Thanks a ton for advice and direction.

 

[Scott O'Kashan]

Welcome to the Corolla Forum! :thumbsup::clap::thumbup::thumbup1::balloon: :rockon:

You are quite welcome for the help this great forum provides. There are a lot of super people here that enjoy helping others with their cars. Hats off to them! :thumbsup:


Below is the troubleshooting chart for the P0420 trouble code. Note it doesn't list an oxygen sensor as one of the possible causes.

Over the 86,000 mile life of your car, have the spark plugs ever been replaced? If not, it would be a good idea to visually check them. That's a long way for a spark plug to go. If they need replacing, I strongly recommend NGK spark plugs.

Here is a link to the NGK spark plug chart that shows you what good or bad spark plugs look like -

http://ngksparkplugs.com/tech_support/spark_plugs/faqs/faqread.asp



Here is an NGK video showing you how to read a spark plug -

If the catalytic converter is bad, I do believe they have a 100,000 mile warranty.

http://engine-codes.com/p0420_toyota.html

P0420 Toyota

P0420 Toyota - Catalyst System Efficiency Below Threshold Bank 1

Possible causes
- Three way catalyst converter Bank 1
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM)

Tech notes
As the code description implies the P0420 code means that the vehicle's control module has detected that the three-way catalytic converter is not working properly (is not as efficient as the factory is expecting). Replacing the oxygen (O2) sensors may sometimes fix the code, but in most cases the catalytic convert needs to be replaced to fix the problem. If the P0420 code is combined with other codes, try fixing the other codes first.

When is the code detected.
- Three way catalytic converter Bank 1 does not operate properly.
- Three way catalyst converter Bank 1 does not have enough oxygen storage capacity.
Possible symptoms
- Engine Light ON (or Service Engine Soon Warning Light)
P0420 Toyota Description
The Engine Control Module (ECM) monitors the switching frequency ratio of heated oxygen sensors 1 (front O2 sensor) and heated oxygen sensors 2 (rear O2 sensor).
A three way catalyst converter (Manifold) with high oxygen storage capacity will indicate a low switching frequency of heated oxygen sensor 2. As oxygen storage capacity decreases, the heated oxygen sensor 2 switching frequency will increase.
When the frequency ratio of heated oxygen sensors 1 and 2 approaches a specified limit value, the three way catalyst malfunction is diagnosed.

Read more: http://engine-codes.com/p0420_toyota.html#ixzz3C9gbEmDI
​

 

[Scott O'Kashan]

Here are some NGK spark plug videos on how to replace spark plugs -

 

[Scott O'Kashan]

Which NGK spark plugs to use? The below video will provide you solid information. I personally prefer the cutting edge technology NGK Iridium IX spark plugs.

 

[Scott O'Kashan]

Have You Been NGK'd?

Have you been NGK'd? :blink::thumbsup::laughing::lol:

 

[Scott O'Kashan]

P0420 How To Diagnose A Bad Catalytic Converter -EricTheCarGuy

P0420 How To Diagnose A Bad Catalytic Converter -EricTheCarGuy

 

[Scott O'Kashan]

How To Check Fuel Injectors

How To Check Fuel Injectors

 

[Scott O'Kashan]

Finding Engine Vacuum Leaks With A Cigar

Finding Engine Vacuum Leaks With A Cigar

 

[up&down]

Scott,

Do you think bad spark plugs could throw a P0420 code? Maybe if all the fuel is not burned and it goes out the exhaust?

Thanks for all the tips up to now.

I just heard from the mechanic. He said both O2 sensors were bad and the cat converter. Is that even possible for all three to be bad at the same time? Seems like a small probability. Maybe he's just trying spray and pray for the fix.

Thanks again.

 

[Scott O'Kashan]

As I mentioned I think the catalytic converter has a 100,000 mile warranty and Toyota will replace it at no charge. Call your local Toyota dealer and inquire.

If the oxygen sensors were bad, they could caused the catalytic converter to fail.

Watch the video above on diagnosing a catalytic converter and then as your automotive technician how they diagnosed the catalytic converter.

The list for the possible causes of a P0420 trouble code include spark plugs. Have they been replaced in the past 86,000 miles or are they the original plugs?

 

[up&down]

Scott,

I'll call the local dealer about the warranty.

I'm not sure about the spark plugs. Just married. Added responsibilities. Replacing the spark plugs would be good general maintenance if I don't know. It's less than $40 for the four.

Thanks man.

Quickly, I need to replace struts and lower control arm. Which should I replace first for ease of order of operations?

Are NAPA complete struts acceptable or should I go OEM or something else?

 

[Scott O'Kashan]

Well the struts put pressure on the lower control arm, yes? So I'd think you'd have to remove them first. Is the lower control arm bad in some way?

NAPA usually offers decent quality parts. Check the box to make sure they aren't made in China. If they are, in my personal opinion, that is something you want to avoid, big time!

I personally like Monroe struts. Advance Auto Parts sells the entire strut, coil spring and strut plate all in one unit. It's referred to as a Quick Strut.

After replacing the struts a 4-wheel alignment needs to be done or the tires will wear out prematurely.

 

[IFMJohn]

Any parts store that sells monroe struts should be able to get the quick struts. When I worked at oreillys, there was only one instance where I couldn't get the quick strut for the customer within 24 hours and it was for some new-er audi...

 

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Do you guys recommend spending the few extra dollars and getting the quick strut instead of just the shock and having to use the coil spring depressor, etc.? Save time but not money.

And the control arm bushings are getting rough. They're starting to rust holes through them too.

What else do you recommend suspension wise while I'm under with grease on my arms?

Thanks a ton.

 

[IFMJohn]

Do you guys recommend spending the few extra dollars and getting the quick strut instead of just the shock and having to use the coil spring depressor, etc.? Save time but not money.

And the control arm bushings are getting rough. They're starting to rust holes through them too.

What else do you recommend suspension wise while I'm under with grease on my arms?

Thanks a ton.

I'd do the quick strut. You get new struts but you also get fresh Springs. Plus if you don't know what you're doing with a coil spring compressor is dangerous. If you aren't going to go the quick strut route, I recommend that you bring your struts assemblies to a shop and pay them to swap the springs onto the new struts.

With the price of lower control arms with bushings pre-installed, it's almost not worth it to buy individual bushings.

That should be good. I can't think of anything else that I would recommend while you're in there.

Oil change? Transmission fluid? Coolant?

 

[Scott O'Kashan]

The Monroe Quick Strut is a quality unit and many auto parts stores have rebates when you buy a set of four. Here is a link to the Advance Auto Parts website and the Monroe Quick Strut for your 2002 Corolla -

http://shop.advanceautoparts.com/p/...1-P?navigationPath=L1*14921|L2*15010|L3*15732

There is an economy version of this that I highly suspect is made in China. In my opinion, you don't want made in China parts in your car, even if they were free.

The Monroe Quick Strut not only comes with a new strut and coil spring, but also a new strut bearing plate, which will help ensure smooth, quiet steering as the bearings are brand new so the strut will turn easily and quietly when the steering wheel is turned. Old strut plates do tend to wear out and/or have the bearings rust, which causes problems.

With the Monroe Quick Strut, you are basically installing a brand new suspension. At the Advance Auto Parts website, they also have discounts that apply and will save you money.

While you're working on the suspension, check the front anti-sway bar end links. These have rubber components and over time tend to deteriorate, crack and slowly fall apart. They are not hard to replace. Below is the Advance Auto Parts link for a quality Moog kit. Avoid made in China parts like the plague!

http://shop.advanceautoparts.com/p/moog-sway-bar-link-kit-k90124/20517810-P?searchTerm=sway+bar

John is right on the money with warning you about the coil spring compressor that is needed if you only change the struts. I have seen professionally trained automotive technicians have the coil spring compressor slip and the spring comes flying out, or just moves and breaks someone's hand! That coil spring has hundreds of pounds per square inch of stored energy in it and if it slips out of the coil spring compressor, the result can be a very dangerous situation.

 

[IFMJohn]

I was in high school when some kid was using an impact gun on the coil spring compressors. He shot the coil spring across the shop. They literally go off like a gunshot. It could easily kill or maim someone

 

[Donabed Kopoian]

I was in high school when some kid was using an impact gun on the coil spring compressors. He shot the coil spring across the shop. They literally go off like a gunshot. It could easily kill or maim someone

I've seen video of them digging into trees. Coil springs aren't a joke.

And an impact gun? For the love of God...

 

[Donabed Kopoian]

Bad spark plugs that are missing will put unburned fuel in the catalytic converter. That fuel burns off when it hits the precious metals in there, and tricks the downstream HO2S into thinking that the catalytic converter isn't working right. A bad upstream HO2S can cause the same thing if it is suckering the engine into running really rich, but usually, other codes will accompany (such as a misfire code). Fuel injectors that aren't spraying properly can cause missing as well.

If the engine is running top notch and there are no other codes that accompany the P0420, then I would say the catalytic converter wore early, but you'd want that diagnosed first. If they die early, it is usually caused from physical damage, an ignition miss, or a defect. I believe it is actually federal law to warranty them for 100,000 miles.

As far as the suspension goes, before you take the tires off ... move the tire as if you are steering left to right. If there is play there, then the outer-tie rods are worn out. If you would move the tire top to bottom, that would show a bad ball joint or upper strut mount, but you plan on replacing the control arm anyway ... and then pull the tire in and out. Play there signifies a bad bearing. Also check your brakes, and check the condition of the sway-bar bushings and the sway-bar end links to verify that nothing else is worn.

 

[IFMJohn]

I've seen video of them digging into trees. Coil springs aren't a joke.

And an impact gun? For the love of God...

On air brake systems they use a spring to apply the parking brake. Want to guess what everyone calls it?

The death spring.

 

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Wow. Thanks to all for your input on this. I've done all this on my Tacoma but the Corolla will be new potatoes. Thanks for the advice on sway bar links. I remembered changing those on my Tacoma while I was in there so I decided to make the purchase for the links as well.

I've never replaced control arms though. Do they come with everything I need? Just unbolt the old- bolt in the new?

The ball joint boots, tie rod boots, and tie rod ends are in good shape.

One last question. Can the sloppy suspension components make tires wear unevenly?

Thanks again. Y'all rock!

 

[Scott O'Kashan]

See? I told you there are some very good people in this forum. :thumbsup::yes:

Before leaving the auto parts store, ask to make sure the control arms are equipped with everything you'll need. They should be.

Yes, any play in the suspension components will cause the tires to wear unevenly and prematurely. An automotive technician can't properly align a vehicle that has worn suspension parts, i.e. a tie rod end.

When all the work you are doing is completed, be sure to get a four-wheel alignment completed immediately or premature tire wear will occur. If you wait to have this done, wear patterns will develop in the tire and then the tires will wear out faster.

Make sure you are provided a printout of the before and after alignment settings so you can see how far out of alignment the car was, what it is set to now to verify it has been aligned properly and just to make certain the alignment was even completed. There are a lot of dishonest auto centers out there, so beware!

 

[IFMJohn]

You can get bare control arms or loaded control arms. By that I mean a control arm that is just the metal peice or the control arm with the bushings and lower ball joint pre-installed. Make sure that you're getting what I call the loaded control arms. Also, I'd get moog or OEM. Don't buy the el-cheapo store brand. If you go to oreillys, Import Direct is a good brand also. Most import direct parts are the factory OEM part from the manufacturer who produced the part for toyota. They rebox them as oreilly's premium store brand and resell them.

 

[Donabed Kopoian]

Most control arms now come loaded, but make sure. It is straight forward. Three bolts and nuts to remove, old arm out, new arm in.

Now, there IS a proper procedure for this. Get the bolts in there hand tight, get your suspension back together (torque the ball joint and the two bolts for the strut, etc.) and get your tires on. Place a couple blocks of wood under the tires so that you can get under the car, and lower the car onto the blocks of wood (make sure they are wide and long so that the car is stable).

Torque the lug nuts on the tires, then torque the the 3 control arm bolts. This is referred to as setting the pre-load on your control arm bushings. If you torque the control arm bolts while the suspension is fully extended ... you will trash the new bushings quick.

 

[Scott O'Kashan]

up&down - So what's the word on the true condition of the catalytic converter? Did your automotive technician diagnose it the way EricTheCarGuy does in his video? Did you contact Toyota yet about the catalytic converter warranty? Per federal law, catalytic converters have a 100,000 mile warranty and they aren't cheap so this is worth pursuing.

There's another Corolla Forum member here that was charged $650 for a new catalytic convertor by a dishonest auto center that just should have referred him to a Toyota dealers Service Dept. for a free warranty on the catalytic converter. I suggest he contact Toyota and submit his receipt for the catalytic converter and it was a little bit of a back and forth situation, but Toyota eventually reimbursed him. :thumbsup:

By the way, when it comes to great tips for automotive repair, it's good practice to search YouTube.com using Keywords, Eric, Strut replacement, or what have you. I've been in the automotive industry for many years and no one knows it all, but Eric is pretty close and he has an ability to explain automotive repair in a down to earth way that anyone can understand. If he was available to work in my auto center, I'd hire him in an instant!

 

[up&down]

Thanks again for all the advice.

True condition of cat converter is still out. I just replaced the spark plugs tonight. The downstream O2 sensor will have to wait until tomorrow. It's a real PITA. The plugs were worn out for sure but all had the healthy signs of proper combustion in each cylinder.

Tomorrow I'll finish replacing the downstream O2 sensor and get started on the struts.

The control arms are made in China. I think I'm going to return them for something else. MOOG?

Is it really necessary to lower the vehicle before torquing the control arm bolts?

If the cat is bad I'll have time to get the warranty on it. Only 86K on this ride.

Of note is that the CEL takes a while to come on after it is reset. It took 3 days last time. What does it mean if it takes so long to come on? I figure it should just come right back on if something is wrong.

Strut bolts soaked in PB Blaster tonight and ready for breaking tomorrow afternoon after work.

 

[up&down]

4 wheel alignment?

Can the rear wheels be adjusted too? Just camber?

The sway bar links are MOOG. Should the control arms be MOOG too?

 

[Scott O'Kashan]

The oxygen sensor is not listed as one of the causes of a P0420 trouble code.

Which spark plugs did you use? I hope you gapped them. I hope the spark plug videos I posted for you were of help.

Made in China parts...:blink::icon_eek:...hold on...:sick::sick::sick:...:thumbdown::thumbdown:

Moog on the other hand is excellent quality and I can highly recommend them.

You can pick up a scanner tool like EricTheCarGuy used in his catalytic converter diagnosis video, from Advance Auto Parts or most automotive parts stores and diagnose it yourself.

I'm sure Donabed will tell you the answer to your control arm question. I've never personally replaced one.

The Check Engine Light can many times take many days to come back on to let you about a problem because the onboard computer monitors have not reset yet. Once they do, then they can do their normal job again. It can take several days for the monitors to reset. In this day and age of computerized cars, having a scanner diagnostic tool like EricTheCarGuy has can pay for itself many times over. This is a tool you will use over and over again. Here is a good one from Advance Auto Parts -

http://shop.advanceautoparts.com/p/...ol-cp9185/16980007-P?searchTerm=code+scanners

Here is a video by Eric on automotive diagnostic scanners. Enjoy. :thumbsup:

 

[Scott O'Kashan]

4 wheel alignment?

Can the rear wheels be adjusted too? Just camber?

The sway bar links are MOOG. Should the control arms be MOOG too?

Yes, all front wheel drive cars require four-wheel alignments. The rear alignment can be adjusted too.

If it were my car, I'd stick with Moog for everything. Moog parts cost a bit more, but that's because they are better and will last longer, saving you money, frustration and headaches down the road. :thumbsup:

 

[Scott O'Kashan]

What Makes Moog Parts Superior?

 

[Donabed Kopoian]

Some codes require three failures in a row to trigger a CEL. Usually a catalyst efficiency code will not return instantly (by three failures, I mean three times for the car to warm up to operating temperature, have been shut off, cooled off, and that cycle repeated two more times).

Don't waste your money on the Downstream HO2S. I only replace those if the code says that the sensor has failed (and I have eliminated all other possibilities). The fact that P0420 showed up actually means that your Downstream HO2S is reading properly.

Yes, it is necessary to torque the control arm bolts with the car at normal attitude position.

Twist your arm fully right, then have someone grab the middle of your forearm, and twist your arm back straight ... now pretend your flesh is the control arm bushings. That's what happens when you torque the control arm bolts with the suspension fully extended.

When I had my '82 GT, I put 200 pounds of weights on each strut tower when I torqued down the control arm bolts. Gives the car slightly more bound than rebound, but it is isn't exactly gentle on bushings.

 

[up&down]

So the Drive Works control arms look (in the hand) to be higher quality than the MOOGs. They cost more too. Any thoughts?

I'm hearing a lot of new negative stuff on MOOG.

Thanks for the word on the CEL. That makes sense. Thinking back, it was coming on after exactly three temp up/temp down cycles with cranking in between.

I feel foolish for replacing the downstream O2 sensor now. I've gone through all the trouble to get to the plug and remove it. It's another 10 mins work today after work. Only silver lining is that it will be new and last a while. Damn!

I hope to start on the struts today starting in the back.

So to tighten the control arms I need to lower the car back down on a jack stand under the control arm. Is that right? Will this damage the control arm?

Putting wood blocks under tires seems sketchy what with the tires being round and having a tendency to move.

Any other input on how to load the control arm before torquing?

And is a torque wrench necessary or is "just tight" acceptable? How much is a good torque wrench (not top of the line or anything)?

Everyone on this forum rocks. I can't tell you how much I've learned in less than a week. What did we do before forums?

 

[IFMJohn]

Ive never heard of that brand of control arm so I cannot speak to its quality.

That will not damage the control arm.

Chock the wheels you're leaving on the ground and set the tires on wood blocks. It won't go anywhere.

A torque wrench is necessary. In my experience, the cheap parts store torque wrenches are plenty accurate when you first open them. They are more prone to losing their calibration with time than a higher end torque wrench. You can get them for the $20-30 range.

Independent AMSOIL Dealer, Contact me to get the world's best oil for prices lower than brands like Mobil1 and Royal Purple!

GoldMedalSyntheticOils.com

 

[Scott O'Kashan]

Every single, "Drive Works", part I've seen is stamped, "Made in China".

Moog is a suspension industry standard. Their quality is second to none.

 

[Donabed Kopoian]

I have had great luck with Moog when I use them.

I wouldn't put a jack stand under the control arm because the jack won't be flush on it. Using long, wide blocks of wood, putting the car in gear, setting the e-brake, and chocking the rear wheels is far safer.

And yes, it is mandatory to torque suspension. Using the wrong torque can damage bushings or allow the bolts to work loose.

 

[Donabed Kopoian]

If you can get ahold of two cinder blocks to stick under each of the tires, that would work as well (provided that the concrete is in good shape).

When I did mine, I went to Home Depot and found a 4x6 post that I used. Ended up giving me enough room to get under there, and I'm not exactly small.

 

[up&down]

All,

Took a stab at starting on the rear struts. I'm from GA and have never worked on a car that was driven in salt. What difference. Fasteners are shot. I spent more time with a hack saw and drill than I did with wrenches and sockets. Finally got the driver side rear strut in. Noticed the sway bar links in back needed replacing too. Got MOOGs for that.

And you have to disconnect the brake line to get the strut out. Who designed that for crying out loud. Why not make a tab for it to slide into instead of a closed hole that you have to thread an open brake line through. An added step of brake bleeding to this headache.

I just keep telling myself I'm saving 2 Gs by doing this myself.

Thanks again to all. I'll keep this thread updated with the strut and control arm replacement as well as the final story on the P0420 code and catalytic converter situation.

 

[Donabed Kopoian]

Good luck with it!

 

[up&down]

Whew! Rust is a PITA! All four struts and all four sway bar links complete. Control arm bushings looked fine. It's at the shop now getting a four wheel alignment, a bent wheel straitened, and wheels balanced.

Still looking for the CEL to come back on with the cat converter issue. New plugs and downstream O2 sensor. If it comes back there will be a call to Toyota to see if a warranty covers it.

I'll update as things progress. Hopefully I'll write back in a a few days saying the CEl is still off. One can hope...

 

[Scott O'Kashan]

You've done a lot of work. Congratulations! Your lady is very lucky to have someone care so much about her! :thumbsup: I hope we all helped out.

Which struts did you decide to go with? I'll bet that Corolla rides like a new car now!

By the way, straighten a bent wheel? How did they do that? When metal is bent, it becomes weaker.

 

[IFMJohn]

Fyi, I would be highly surprised if toyota warranties a CAT without a certified toyota tech diagnosing it. You'll most likely be on the hook to pay for diagnosis even if the cat is the issue.

Independent AMSOIL Dealer, Contact me to get the world's best oil for prices lower than brands like Mobil1 and Royal Purple!

GoldMedalSyntheticOils.com

 

[Scott O'Kashan]

Remember, it's not just the catalytic converter that may be the problem.

http://engine-codes.com/p0420_toyota.html

P0420 Toyota

P0420 Toyota - Catalyst System Efficiency Below Threshold Bank 1

Possible causes
- Three way catalyst converter Bank 1
- Exhaust tube
- Intake air leaks
- Fuel injectors may be faulty
- Fuel injector leaks
- Spark plugs may be faulty
- Improper ignition timing
- Engine Control Module (ECM)

 

[Scott O'Kashan]

For Toyota to warranty a defective catalytic converter, yes a certified Toyota automotive technician will need to diagnose that. I don't think they'd make you pay for the diagnostic time though if the catalytic converter is indeed defective, as that should be covered under warranty too.

 

[up&down]

For basic steel wheels they heat it up a bit and give it some soft shots with a ball peen hammer. Nothing major. It was small. I suggest buying a new wheel if it is a major bent section. This was only 2 or 3 inches.

 

[Scott O'Kashan]

I'm really surprised they'd take on the legal liability of that. In many years in the auto repair/maintenance business, I've never seen anyone do that.

 

[Scott O'Kashan]

Which struts did you decide to go with? I'll bet that Corolla rides like a new car now!

 

[up&down]

Monroe. It feels awesome now. RR tracks feel like nothing.

It's funny how bad things get that wear gradually like shocks. You realize how bad they were once you replace them.

Thanks all.

I'll keep the CEL and cat updates coming as I learn.

 

[up&down]

All,

It's been over two weeks since I replaced the spark plugs and almost two weeks since I replaced the downstream O2 sensor. I drove it all the way to Harrisburg, PA and back over the weekend. No CEL! Do you think I'm in the clear or should I hold off on the champagne for a couple of more weeks?

Questions.
1) Do y'all agree with replacing O2 sensors at 80K as preventative maintenance? Some say the get "lazy". Some say just wait until it fails.

2) Even after replacing all four struts and all four sway bar links and getting it aligned and tires balanced I still have a bad rotational road noise. It's tire, wheel, or brake related I think. At high speeds you can feel it through the brake pedal with light pulsing. The noise increases in frequency as the car goes faster so it has to be something in or near wheels, tires, brakes, etc. Tranny issues would change frequency when the car shifts, right? She rides smooth as silk though. There is no feedback in the seat or the steering wheel from this noise.

If it were tire related I shouldn't feel it through the brake pedal, right?

The brakes were done less than a year ago. Could the rotors be out of true already?

Any other ideas to check for?

 

[Kev250R]

If the Check Engine light has stayed-off for the past two weeks I'd say you're in the clear. Sometimes a code can still be in there without illuminating the light but it's not likely.

1) It's not a bad idea, probably over-kill though. I think it's listed as recommended maintenance in the book for my '93 Toyota T100. If nothing else doing them early means they *should* be easier to remove because their less likely to be rusted-in place. I waited until 150K to do the ones on my P/U and one was basically rusted in-place, and this is on a truck which has never seen a salted road.

2) The vibration may be related to the wheel which you had straightned with a hammer. I slightly bent a wheel on my truck once and from then on, despite how many wheel weights were on it, when it was on the front it gave me a slight wobble at highway speeds. When it was in the back I didn't notice it so try rotating your tires and see if that makes any change.

With brakes it all depends on how hard you are on them and how many times the rotors have been turned (makes them thinner and easier to warp).

Kevin

 

[up&down]

Kevin,

Thanks for the words.

There is no wobble on the steering wheel though. The car tracks straight and smooth as silk. It's just the sound and the feel in the brake pedal when applied at hwy speeds.

Thanks.