I have scanned my 98' SS to diagnose a stutter during low rpms. I have the Texas Speed 228/228 .588/.588 cam without a tune. I knew my problem is in the tune or my o2 sensors. The codes are as follows.

PO135-O2 heater circuit B1S1 (Bank 1 sensor 1)

PO153-O2 circuit slow response B2S1

PO154-O2 Circuit no activity detected B2S1

PO155-O2 heater circuit B2S1

P1154-? another code for the B2S1 sensor

So looking at these, the drivers side o2 sensor doesn't heat up fast enough, but works fine while the passenger side looks dead. I am going to replace it, but want to know if I should do the same for the drivers side?

Second question, would a mail in tune by madz28 be worth the price/effort? I don't have access to a dyno tune where I live, so that's out of the question. Thanks for the help.

 

The heating element is probably just dead, replace sensor and it should be fine.

 

Vamp, were the Pacesetter's installed recently, thinking about O2's fouled by new coating, burnt wires, or maybe a spliced harness on the O2 side instead of the PCM side. By the way you can check heaters, should have +12V between pink and black (ground) with ign on, all four O2's use the same 20a fuse in the under hood fuse/relay box. Also with sensor disconnected there s/b 5-7 ohms between pink and black wires (heater coil).

 

I bought the car almost two years ago with the headers installed. The previous owner had the same problem but never troubleshooted it. The headers very well could have fouled the o2 sensors. How and why are not an issue though, although I didn't check for a bad splice or fuse and will do so today.

My question was if I should change out the sensor if it has a bad heating element? I don't beleive it matters a whole lot.

Second still, I bought the mail in tune for my z28 when I installed the headers and noticed not one little bit of difference. The SS has the cam though, so maybe I would this time but I am worried about wasting hundreds of dollars on another mail in tune. Anybody have some insight on this?

 

If your o2's are not working the PCM will stay in open loop. Correct O2 operation and running in closed loop is a prerequisite to a good tune. Don't waist any money on a tune without getting the o2's straightened out. Your o2's need to get up to 600* F to operate, headers move them further away from the exhaust source therefore the o2 heaters become even more critical w/headers. If the circuit checks out OK AND the wire splice is NOT at the o2 sensor pigtail end then I recommend replacing both sensors at the same time.