navajoDDS

Hey Everyone!

You guys helped me out a few weeks ago with my newly purchased 99. I had a terrible experience with IPS Motorsports here in Columbus. They finally gave me a refund and we went our separate ways. I was also looking for tires and ended up going with the new Cooper CS5 Ultra Touring bc they were offering a rebate and i got them installed for about $365. They've been great, but I found out one of my wheels are slightly bent, so I can add that to my to do list. Not sure if I'm better off buying a used wheel off ebay/junkyard or having a local company recondition it. It's definitely causing some shaking.

When I was getting my tires put on, they told me my A/C and Power Steering belts are on their way out, Are those a relatively simple DIY?

Now on to the heart of the matter. Last week I got my first CEL. Autozone diagnosed it as p0420 and p0430. These are the bank 1 and 2 O2 sensors right? I've been trying to do some research on here to see what I should do. What are the chances it's just the sensors vs the catalytic converter that are bad? I just put a 16 oz can of seafoam in a half tank of gas and plan on checking/changing the spark plugs next week. It sounds like I should also clean the EGR port but it seems a bit daunting to a noob like me. I'm sure I can figure it out though.

What's the best way to figure out if I need to replace the O2 sensors or cat converter? Or could a good seafoam treatment help do the trick?

cominfromafar

Belts you can absolutely do yourself. Just don't over-tighten the Power steering belt because it will cause premature failure of the bearings in the pump, which will sound like a metallic whine, sort of like when your PS fluid is low. Check the factory service manual, page 17-17 for the deflection method of setting belt tension. I used a bathroom scale to "feel" what pushing 22 lbs felt like on my index finger tip, and went with that. The AC+Alternator belt uses an auto tensioner, no adjustment needed on your part.

Others will chime in on your codes. I don't have any experience with them...yet.

TLZINE99

U can try EricthecarDude's Catalytic converter laquer thinner trick. lol

01tl4tl

seafoam cleans the O2 sensor (more likely failure) and the cat when used in gas tank
Forget the bank number blah- the front sensor monitors outgoing exhaust gas and adjust engine operation to change fuel, air, timing mixtures,
the rear or post cat sensor makes sure the cat is working by measuring outgoing gas are at correct reading

more than 70-100kmiles on car = its ready for NGK spark plugs, an egr/intake manifold cleaning and some belts = totally normal things

Ck the ac belt tensioner while you have everything loose/apart- its very common wearout and the strange noise will eventually drive you crazy~ (at least that's my excuse!)

Our DIY section threads are written so the newest noob can get the job done
Local ziners can be found in the Regions section- for in person diy assistance
what you spend in basic tools is less than 1 job at shop!
and it will be done RIGHT because you followed directions EXACTLY as written on here- knowing its been done thousands of times using this method = it works
Versus shop/tech who may never have done a particular job and YOU being a guinea pig is never a good thing!

navajoDDS

Yesterday was day 3 on my seafoam treatment, and on my way to campus the CEL went off. It hasn't come back on yet. What are the odds of the seafoam cleaning the sensors? Should I worry about the sensors even if the CEL doesn't come back on? I've noticed some smoother shifting as well. Good stuff. I'm still planning on doing the spark plugs and belts, so I'll keep an eye on it. So far I'm pretty impressed with the seafoam. I have another bottle of it, should I use it right away (my gas light turned on today) or do a half tank of gas, drive, and add the seafoam on the next fill-up?

01tl4tl

you can add it to the next half tank,
the idea is to get as much hot time/over 30 minutes drive for best results,
heat and time are seafoams friends
ok to run the tank down another 30 miles after light comes on,,get all the seafoam full strength useage possible = try to keep a 2 oz foam per gal fuel ratio, more than 2 pr 1 doesn't work better, just waste money

still need to clean your TB air inlet plate inside TB throat with carb cleaner or deep creep (seafoam aerosol)

over the month you will get the full effects of the cleaning and yes it does clean the O2 and cat so it can turn off the cel,,,wont hurt to reck codes- do a reset with CLOCK fuse and see how it goes

make sure to use correct ngk $8 each
seafoam in gas will not hurt them- new or old -in any way!

thoiboi

Gen 2 TL's (like my 6th gen accord v6) are notoroious for having P0420. Usually people jump to 02 but if you read up P0420 is the cat going out. You can buy new o2 sensors but that's just delaying the inevitable. I ended up just getting a new cat (pricey, i know ) but no more P0420. o2 sensors have yet to been replaced. (1999 with 249K)

01tl4tl

your car would run much better on fresh front O2 sensor with your high miles
other makes of cars require new o2 at 50kmiles!

cat failure for us is rare and may be linked to use of 87 octane fuel OR sustained high speed driving can overheat it

Aftermarket and performance cats are a good deal thru 2 of our sponsoring vendors
or local shop, no need for an oe cat on 14 year old car

Denso brand is the OE supplier of the O2 sensors and avail everywhere, not too many $$ and pays you back in fuel gain

3.2TLc

If indeed ya have a bad or plugged cat, you'll know as the motor will run poorly, suck gas and smell bad.

01tl4tl

that rotten egg smell is a big clue, bang on cat with a rubber hammer to ck for loose- broken material inside, ck cat temp with one of those little $25 point and read temp gauges

Codes are CLUES and not always a diagnosis in themselves