liqidvenom

iTrader: (6)

i kno that im still n/a but i have a question about a cel that i pulled and i cant get an answer anywhere else. i got code 0702 which is (Diagnostic Trouble Code 0702 points to a problem with the three-way Catalytic Converter.

The Cat is one of the principal components of the emissions control system. The Engine Control Module monitors the signals from the two front Oxygen Sensors and the one rear Oxygen Sensor. The signal frequency of each sensor indicates something about the condition of that sensor. A comparison of the frequency of the front sensors with the rear sensor indicates something about the condition of the Cat.

This malfunction was detected when the ratio of the signal frequency from the right bank front Oxygen Sensor to the signal frequency of the rear Oxygen Sensor exceeded a critical threshold value. This indicates that the Cat does not have enough oxygen storage capacity. The right cylinder bank is also called the rear bank. It is cylinders 1,3,5. Possible causes of this DTC include ...
- Three-way catalyst
- Exhaust tube
- Intake air leaks
- Fuel injectors
- Spark plugs
- Ignition timing )

i dont know if its my hi-flo cat that maybe causeing it or it my y-pipe somehow is behind it. my non -maxima friends think that it may be my hi-flo cat isnt flowing enough air so i bought a straight piep to replace it but i dont want to put it on if thats not really the culprit. I really need some help wit this because want to solve this problem soon.

Thanks again for any replys and i'm sorry for posting here but i figure you guys may have a better chance at giving me an answer since the guys inthe 4th gen room dont have a clue.
Will

liqidvenom

iTrader: (6)

i hope that somebody may have an answer to this, or maybe im the first one to get this kind of code on my car?

IceY2K1

iTrader: (3)

My *GUESS* is that your y-pipe removed a precat(?) and your high-flow cat isn't doing much, so your ECU isn't liking it.

IIRC, '98s are fed spec with an 02-sensor on each bank and one behind the main cat, correct? If so, you could try a different cat or look into an 02-simulator or maybe a Split Second black box for tricking the ECU.

However, don't 4th gens run ypipes with straight pipes without a CEL?

Just trying to help give some ideas here.

Redmax

iTrader: (20)

hey ice, what does iirc mean? sorry to ***** this thread

IceY2K1

iTrader: (3)

If
I
Recall or Remember???
Correctly

liqidvenom

iTrader: (6)

thanx i just got the straight pipe and i'm gonna give it a chance.

Stephen Max

iTrader: (59)

A rear O2 sensor code is pretty common for 4th gens running test pipes, as is expected. (Interestingly, I don't get the code with the JWT ecu - another little bonus for going with JWT.) I agree it could be the high flow cat doesn't make enough of a difference in emissions to satisfy the ecu's criteria. If you're getting it now, you definitely will have it if you install the test pipe. You can get rid of the CEL by getting an O2 sensor simulator from Baker Electronics (what Icey referred to above), which are sold on ebay.

ref: http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEBWA%3AIT

This was talked about in the 4th gen forums a couple of weeks ago.

IceY2K1

iTrader: (3)

Yeah, without a CAT of some sort, you're going to throw a CEL.

That's the purpose of the rear 02, ie telling when one or more cats goes bad. You're mimicking that by removing them or putting a high-flow version in, which honestly probably doesn't do squat.

FYI, Cattman is working on a new high-flow cat that can still pass emissions. Maybe that will save these CEL from going off, I don't know.

pawnstar12

i have a 3" hi flow and i throw 0702 at least once a month.