LT1Camarogirl

alright, so before i begin let me note that i have searched this topic and couldnt really find a thread that matched my question...so here goes...
alright, so, i've got long tubes. with the air and egr hookups. there are the 2 bungs in the rear of these things, and then i've got an ory hooked up. i should note that i have the rear o2 simulators in and they work fine (no codes popping up for a year)...so ever since i installed the headers, i've had to change the o2s probably twice now, i used bosch and ntk ones. now, when i pulled them, they were black. so obviously my car is running rich...anyways, i'm not sure how to fix that fact but i'm really sick of having my ses light come on and having to replace the o2s...now for the question:can i get simulators for the front as long as i fix the rich issue? or should i clean the ones in there right now, and install an o2 sensor simulator fitting...which would allow me to still use them, but they wouldn't be in direct flow of said exhaust...

Injuneer

The pre-cat O2 sensors control the A/F ratio in closed loop. If you remove the pre-cat sensors, you will have to have the PCM set up for an open-loop tune. Will run OK with a good tune, but the PCM will have lost the ability to correct the A/F ratio in response to changes in engine condition, sensors, etc. If you switch to an open-loop tune, you no longer need any O2 sensors or simulators. The tuner would simply turn off all the O2 codes, which aren't going to set anyway in open loop.

If you move the pre-cat sensors out of the exhaust stream, and keep running a closed loop tune, it will probably produce extremely erratic results, depending on whether the exhaust is backwashing into the bungs or not.

Find out why its running rich, rather than trying to ignore the problem by deleting the O2 sensors. When your SES light comes on, what are the codes you are seeing?

Have you tried running without the Hypertech "power program"?

What did you use to extend the harness to the O2 sensor locations on the long tubes?

Most people have the best results with AC/Delco (now Delphi) O2 sensors.

LT1Camarogirl

the codes i saw were p0131 and p0134...
i haven't pulled any of the plugs yet to see exactly how rich i am running, but i guess it would be pretty bad if the o2s are black after 6 months of use.
i used the wire supplied with the headers to extend the harnesses.
i haven't tried taking the hypertech program out, do you think that would help? i'll try it later today if so...
so, what steps should i take in finding out why it runs so rich now? get a stoich meter in there or what?

94zgreenmachine

The coatings on the headers can foul the 02's. Ion recommends using junk ones at start after a coated header install.
With your install on the headers, are you sure you don't have a header leak? Try a mirror to see on the underside of the flange, Do you see black? I had a horrible leak using the Percy's junk. I have since went with these:
http://store.summitracing.com/partde...A3BERL&FROM=MG
Plus you can buy replacement inserts:
http://store.summitracing.com/partde...EAR-29D03B3ERL
A little pricey but these gaskets seal awesome. You can put them on and forget about them ever leaking.

Injuneer

Both those codes are for the driver's side pre-cat sensor. First one is "O2 sensor low" - detects an O2 voltage stationary lean (low signal voltage)condition. Second one is "O2 sensor circuit no activity" - Circuit continuity detects an O2 cricuit open.

Swap the two pre-cat O2 sensors side to side. If the problem follows the O2 sensor to the passenger side (P0151, P0154) its definitley the O2 sensor. If the problem stays on the driver's side, its either the wiring for the sensor, or some sort of major engine problem (misfire, exhaust leak, vacuum leak, etc.) that only affects the driver's side.

If you have access to a wide-band O2 sensor, that would allow you to see if its really running rich. Scanning software will also provide you with info regarding the long term fuel corrections, which are probably elevated as a result of the problem on the driver's side. Looking at the long term corrections for both sides will tell you if its a problem that only affects the driver's side, or one that is affecting both sides.

LT1Camarogirl

funny you mention that, i had a bad ticking for the longest time, and so i went to change the gaskets and replace them with the perceys dead soft aluminum ones and split locks..well halway through the job i discover the split locks are a 1/4" too short and the gaskets were too thick..so i reused the old ones...well, the tick went away, but i havent tried the mirror trick yet...sounds like a good idea, and those gaskets from summit look badass...

good idea, another thought i had was my problem being the wires, i mean, when i was doing 125km/h one day a while back the engine light came on and flashed at me and the car felt like it was lurching almost, i know that's a misfire, but it hasn't happened since and i've been watching my guages like a hawk...so even though there's no misfire code present, just the o2s, it could still be a misfire basically?
unfortunately for me i don't have access to a wideband o2 sensor..when you mentioned scanning software, are you meaning fuel mapping/proper tuning?

94zgreenmachine

DataMaster is only for OBDI.

LT1Camarogirl

never heard of it-is this something shops are gonna have on hand or am i gonna have to find a tuning shop somewhere?

94zgreenmachine

You'll need a laptop.

Here is a link to Datamaster:
http://www.ttspowersystems.com/DataMaster.html

A cable is also necessary:

http://www.ttspowersystems.com/ALDL_cable.html

A little pricey but it also reads codes for the engine and the trans. You can also reset the codes and monitor the engine while running and log runs for later analysis.

LT1Camarogirl

looks like it'd be worth it, but i was kind of hoping for something a little more local than that-just because i'm still amateur at this stuff, and it'd be great for someone who knows what they're doing to do this for me.
i'll do any other mechanical work on my car but when it comes to this computer stuff i turn into a total girl

94zgreenmachine

It is actually fairly easy to use. Don't let it intimidate you, besides, it isn't actually programming rather more of a "monitor" type program. There really isn't anything to mess up.

There are some knowledgeable people on here that could help point you in the right direction as far as what readings should be what i.e. IAC counts, TPS throttle angle, tps volts, etc. It even has a spark knock feature that you can monitor.
I'll see if I can get a screen shot and PM you what the format looks like. Very easy to see and understand.

LT1Camarogirl

i'd be interested to see what that looks like, thanks...
another question: is it worth converting to obd1 to make for easier tuning or no?

94zgreenmachine

I would think any competent tuner should be able to work with either. There are some pros and cons to each. I don't have any tuning experience so I can't say which is easier to do.

Injuneer

DataMaster will not work. Appears the car is a 97 = OBD-II. TTS DataMaster is only for OBD-I. You require something like AutoTap, and that is not free. There are several other OBD-II scanning programs. None of these are for "tuning". A "scanner" isn't for tuning. A scanner allows you to read the engine operating parameters, sensor readings, PCM computed values (injector pulse width, misfire count by cylinder, etc.) and access and clear the trouble codes.

http://www.obdii.com/obdii.html

http://www.digimoto.com/

http://www.obd2.com/

94zgreenmachine

Yeah, I just activated Datamaster on my new laptop and noticed that "little" detail about the years. Sorry for the mix up.