Beeler422

iTrader: (3)

I've got a question here. I bought a 69 camaro that's got an LS2 and a painless performance wiring harness and pcm. It does not have a MAF so I'm assuming this has to be an SD tune. The driver side header has an O2 sensor but the passenger side does not. I'm not a tuner by any means, but if it's not running a MAF, can't I remove both O2s? I can't figure out why they would have have one O2 sensor in there. Thanks.

LSX Power Tuning

iTrader: (4)

You need to have the front (2) O2 sensors to run closed loop so the pcm can adjust the fueling. It is possible to delete all the O2's and run in open loop but then you basically have a fancy carburetor motor with injectors at that point since it will not adjust fueling at all.

gagliano7

The o2 sensor is probably a wideband sensor that is why you only got one.That will send info to the computer so it can make changes on its own. The sensor should go in the drivers side exhaust.

Beeler422

iTrader: (3)

Thanks. Although my question is, if there is no MAF, do I have an SD tune and do the front O2s serve any purpose?

Beeler422

iTrader: (3)

I didn't even think about it being a wideband. Hmmm. How would I verify that?

joecar

Note that the MAF and O2 subsystems are independent of each other...

i.e. there are 4 combinations that you can run:
- CLMAF
- OLMAF
- CLSD
- OLSD

i.e. with your SD tune you can run the front O2S if you want CL trimming.

MAF subsystem does not effect O2 subsystem, and vice-versa
(i.e. MAF and/or VE provides cylinder airmass, O2S provide fuel trimming, regardles of each other).

joecar

You have an SD tune only if:
- the VE table correctly models your engine's cylinder airmass thru-out the operating range;
- a MAF DTC triggers immediately on engine start (without this you will not have SD).

edge04

iTrader: (9)

agreed. probably running open loop during WOT only.

LSX Power Tuning

iTrader: (4)

Your in SD, the front O2's work like normal still.

If its a stock gm computer you dont have a wideband. All the standalone harness's I have seen from painless used stock front O2 sensors. They also just had codes deleted to work in an engine swap. There wasnt any performance changes made to the tune.

Beeler422

iTrader: (3)

Thanks all. I'll try to get it hooked up to hp tuners and see exactly what's going to. my check engine light isn't on so the computer doesnt appear to be bothered by not having an o2 on the passenger side.