2000 z28

[trixie128]

My “Service Engine Soon” light came on so I took it to the dealer. They diagnosed the problem as a bad O2 sensor so I had them repair it. About six months later the same light came back on so I took it to AutoZone and had them do a free diagnosis. They gave me the code (I’ll have to look it up in my records) and told me it was something different than the O2 sensor. I took it back to the dealer and gave them the code and asked them to diagnose the problem. I believe this time it was an “Air Check Valve and Gasket.” I again had them repair the problem. About three months later, the same light came back on. When I got my car back to the dealer that Saturday, the light had gone off again. Since then it has periodically gone on and off over time. Now that it is time for me to get my car inspected, they won’t pass it while the light is on. I decided to try to get it to a shop as soon as the light went off again but ironically, I am running out of time before my sticker expires. Is there any way I can avoid this problem without costly auto repairs? Any suggestions would be greatly appreciated.

[jakeblkSS]

well you could buy a code reader from your local parts store and if the light comes on agin just use the code reader to cleer the codes.

[BlackZ28TTops]

You can always just pull your battery cable, and wait for like 20 mins or so to reset your code. Or their is a writeup to do it with the PCM Bat fuse, but I always have better luck with unhooking the battery. Hope this helps

[jakeblkSS]

Originally Posted by BlackZ28TTops

You can always just pull your battery cable, and wait for like 20 mins or so to reset your code. Or their is a writeup to do it with the PCM Bat fuse, but I always have better luck with unhooking the battery. Hope this helps

Yeah you can unhook the battery but I like to see what the code is if its the same one and such.
If you have a parts store near buy they can check your codes and delete them free in most cases.

[trixie128]

Thanks you guys. I'm gonna give it a try today...we'll see

[Desert Rat]

I've found disconnecting the battery doesn't always clear the codes. O2 sensor codes will stay for at least 3 drives before they clear themselves

The battery trick always worked on my Nissans, but not my Camaro.

Let me ask this...when you throw codes, are they coming when you're at wide open throttle? That's when mine comes on - at about 5k rpms. I'm throwing 02 sensor codes, and have new sensors that I just haven't installed yet.

[Chris]

idk if you can take the bulb out like I did with mine.

I would bring your car to someone else if the problem still isnt fixed yet

[trixie128]

So the trick didn't work and I failed at two places! The code is "P0420 Catalyst System Efficiency Below Threshhold (bank 1)" I made an appt to take it in, but I'm terrified they're gonna try to fuk me outta the O2 sensor money I already paid them to fix. How many O2 sensors are there? 2? I've just never really heard of a Cat converter going out... yet...am I wrong here? I can't imagine it being the problem HERE. I saw someone in a diff room mention a recall on the cat. converter but I looked all over GM and couldn't find anything????The light is on as soon as I turn the key on. HELP PLEASE! I'm going to rip my hair out :-(

[ncz28ragtop]

there are 4 o2 sensors...could be your cat they do clog up sometimes

[BlackZ28TTops]

THere was a service bulletin to replace your cats. I had it done, just ask the dealership, mine was in and out, no charge. Search TSB #05513 Here. Hope this helps!

[trixie128]

Thanks for the help guys. I REALLY appreciate it. Unfortunately, I took it in to the dealer for them to diagnose the problem as a bad cat. converter! $97 diagnostic fee. They said "Sure! We can fix it today! It will be $782 plus tax" OUCH! So I paid the $82 for the "Dealer" synthetic oil change and the $97 diagnostic fee and picked her up. I want to fix her but I just can't afford it right now...not even close! I ended up getting a $100 bootleg sticker in the ghetto and buying myself some time. I feel no hesitation or problems with the car running. Can NOT replacing the cat. converter damage my car? She's the only car I have so if I have to eat out of the garbage for a month to fix her I will! NO JOKE. I bought the car from a Chevy dealer but I bought it used so they said the TSB didn't mean any repairs would be covered. So what's your advice? What should I do in the best interest of THE CAR?

[toofazt]

First off, take your car to Auto Zone next time your check engine light comes on and they'll scan it for free and tell you what's wrong. Just ask for the OBDII scaner.

Not replacing the damaged cat won't mess up your car. It may cause you to fail emission testing though. You can pick up a new cat off thunder racing for $100-$150 if you need to replace it...

[ncz28ragtop]

Originally Posted by trixie128

Thanks for the help guys. I REALLY appreciate it. Unfortunately, I took it in to the dealer for them to diagnose the problem as a bad cat. converter! $97 diagnostic fee. They said "Sure! We can fix it today! It will be $782 plus tax" OUCH! So I paid the $82 for the "Dealer" synthetic oil change and the $97 diagnostic fee and picked her up. I want to fix her but I just can't afford it right now...not even close! I ended up getting a $100 bootleg sticker in the ghetto and buying myself some time. I feel no hesitation or problems with the car running. Can NOT replacing the cat. converter damage my car? She's the only car I have so if I have to eat out of the garbage for a month to fix her I will! NO JOKE. I bought the car from a Chevy dealer but I bought it used so they said the TSB didn't mean any repairs would be covered. So what's your advice? What should I do in the best interest of THE CAR?

stay away from the dealer on repairs if i were u...well stay away from a dealer all together unless you are buying a new car...$782 for a cat change they have lost there mind..you can get a universal one for as low as $60 depending on which one is bad under there...and its nothing to cut the old one and weld a new one in...find u a muffler shop and they can get all this all done for u pretty cheap

[BlackZ28TTops]

Originally Posted by trixie128

I bought the car from a Chevy dealer but I bought it used so they said the TSB didn't mean any repairs would be covered. So what's your advice? What should I do in the best interest of THE CAR?

That's B.S. I bought mine used too, and the dealership covered it, Find a new dealership to take your car too, or a muffler shop, or wherever, just not that place again. They are trying to rip you off.

[trixie128]

Thanks guys. It's pretty disappointing that I can't find ONE decent place to take my car in ALL of Houston. I will never understand why people are so crooked. Thanks again! You all helped more than you know :-)