Cat Delete & Check Engine Light

[cayman]

I did the cat delete and anticipating the 'puter throwing a code, I ordered O2 sims from Casper Electronics. Instead of going ahead and putting them on, I went ahead and drove the car without the sims as there were conflicting thoughts on whether or not the cat delete will throw a code on a '98 RT. According to the manual, there is an upstream and downstream (before & aft of the Cat) O2 sensor. The PCM compares the signal from the two sensors and as the signals become closer to the same, indicating the cat has become inefficient, it throws a code.
I drove the car for some time without the check engine light coming on but finally after about 40 miles it did. So, I went ahead and put the sims on. The light didn't go out but my experience on C5 vettes is that after you fix the issue that caused the light to come on in the first place, the light will go out after a few cycles. I was wondering if this will happen in this case or if I'm going to have to take it to the local Dodge dude to manually clear the code.

 

[AJT]

If you dont have a code reader you can take to an auto parts store & if you find a good guy he will read & clear the code for you.

 

[Ulysses]

my experience on C5 vettes is that after you fix the issue that caused the light to come on in the first place, the light will go out after a few cycles.

That is true for some codes, but not the O2 sensor.

 

[Doug Supercharged Vipers]

Disconnect the battery at the jump post for about a 1/2 hour. The light should go out and you'll be good to go.

Good luck!

 

[stangkilr1]

i have over 100 miles on my 99 gts with no check engine light...

 

[SYNFULL]

Same here on 99 GTS over 1500 miles. I thought a 98 would be good.
Gary

 

[red98RT10]

I have a 98 RT and the light does go off after a while by itself. I just did my cat delete about one month ago and had the same problem!

 

[cayman]

Interesting that on some '98 and newer removing the cats throws a code and on others it doesn't. Theoretically, according to the book that describes the workings of the PCM along with the O2 sensors, it should be throwing a code on any '98 and newer that has a before and aft sensor in relation to the cat?

 

[big-n-italian]

no cats, no sims, no codes.

 

[cayman]

Well, after about 100 miles, the check engine light went out and is now staying out. I guess after a few hundred cycles with no error signals, it goes out. Good.........now I don't have to go to the dealership and get reamed to the tune of 40 bucks like the last time I brought it in to confirm an error code. Five minutes of their time for forty bucks

Thanks all!

 

[Anaconda]

The problem with this is you don't know if the computer is adjusting the A/F without throwing a code, and making your gas mileage ****.

 

[V10SpeedLuvr]

Well, after about 100 miles, the check engine light went out and is now staying out. I guess after a few hundred cycles with no error signals, it goes out. Good.........now I don't have to go to the dealership and get reamed to the tune of 40 bucks like the last time I brought it in to confirm an error code. Five minutes of their time for forty bucks

Thanks all!

You can go to any parts place (Advance auto, autozone, etc) and they'll clear it for free

 

[Matthew Klinger]

I had the exact same situation with my '02. Take it to AutoZone and have them reset the computer and it will clear. They did mine for free.

gtsKlinger

 

[cayman]

The problem with this is you don't know if the computer is adjusting the A/F without throwing a code, and making your gas mileage ****.

It's my understanding though that if a code was thrown because of the cat delete, the PCM doesn't go into limp mode. The check engine light comes on as a reminder to check the code which in turn will tell you that your cat converter needs replaced. The only time the PCM would go into limp mode because of an O2 sensor (operating off of a set of fixed parameters for the A/F mixture) is when a bad signal comes from the front O2 sensor. The rear O2 sensor is there strictly for monitoring the efficiency of the cat converter (as mentioned before, the PCM compares readings of the sensor before the cat and the sensor after the cat). Someone correct me if I'm wrong....................