Service engine soon light

[03c4s]

Newbie here with a question.
I have an 01 TAHOE 5.3l 98k-Mods-K&N and Gibson catback dual side exhaust and Hyperthech program.

Service engine soon light came on, took it to my non dealer mechanic and his diagnosis code reader said it was related to the emission. He replaced the oxygen sensor and said the car needed to be reflashed at the dealer and said the Cats need to be replaced.

Seems funny about the cats needing replacement.

Anybody have any advice on solutions?
tx in advance

 

[Gordo]

try the gas cap seriusly, or take it to autozone for a second opinion it dont cost anything to try.

 

[greengumby]

:iagree:

Also there are 4 - o2 sensors sounds like the mechanic didnt know his head from his feet

 

[Nappers]

have the codes read and check it out. I had a CEL and it was a check valve for the 2nd air injection, 40 bucks later I was good as gold and I have 128,000+ miles on the clock original everything.

May replace the o2 sensors someday for giggles.

I bought the cheapo scanner ($100.00 one at walmart/shmucks etc) and check my own CEL (2 to date) and research it myself. Easy as pie.

Aaron

 

[03c4s]

Appreciate the info, will get a scanner and do my own research.
Checked the gas cap it's good.

 

[JAY DEE]

Man this might sound stupiud but just get a tune up

 

[greengumby]

Before anything else is done get a scanner ..or you'll end up swapping parts for nothing , Also with the 01+ the Dic actually tells yah to check the gas cap if there was an issue. thats what mine did last week ..Let us know what the codes are good luck

 

[03c4s]

The non dealer shop had a code reader, he said it had something to do with the emission system, hence replacing the o2 sensor.
Then he said they needed to take it to the dealer to flash the ecu, and then check it again.
He then added it's probably the Cat that needed to replaced and that would be around 1k. Assuming it's the cat can I used a magnaflow replacement for better flow, I currently have a gibson catback.

 

[Nappers]

did he tell you what the codes were???

post them if he did, I just used my code reader, got the number, researched it and fixed it. Scanner paid for itself on the first use.

 

[03c4s]

Tx, anybody have feedback scanner brands or are they all the same?
Tx again for the help. I'll keep posting on the results.

 

[boostaholic]

Werd post codes and we can find out what the issue is. Might be a catalyst threshold, in that case you may need new cats but then it'd a great time to upgrade to some dynatech longtube headers and highflow cats.

 

[reddemon71]

Appreciate the info, will get a scanner and do my own research.
Checked the gas cap it's good.

just disconnect the battery for about an hour. thats all i do

 

[Yuke2K]

just disconnect the battery for about an hour. thats all i do

All that does is reset the ECM. If he's got a problem, he needs the codes that the computer is throwing so that he can get it corrected. Resetting the ECM is only half the battle.