I just installed my Autometer fuel/air ratio guage today and the rich/lean cycle was very sluggish. It would not move at all, suddenly indicate lean, do one or two swings, and then kind of freeze at a spot in the stoich. range. It would jump every time I stabbed the gas, so I'm sure the guage is working. This indicates a dirty/worn out O2 sensor right? Second part: To install a heated O2 sensor, what application do I get one for, and where do I hook up power for the heater part of it?

 

Yep, Andy, it sounds like your sensor might be a little lazy. It is normal for the sensor to lazy until it goes into closed loop (warms up to operating temperature). Sometimes I have seen when someone replaces their thermostat with a cooler 160 degree one, it might actually not stay in closed loop at idle running soo cool, and needs to be revved up to go back into closed loop .

 

generally any 3 wire sensor wil ldo the job just ask for a 3 or 4 wire universal sensor
wire the heater wire off the fuel pump power wire

 

Thought so... I know about cooler running engines sometimes doing that, so I held it a 2500 for a bit to make sure it got nice and hot,(approx 180 by guage) no effect. Now on the 3 or 4 wire O2 sensor some questions: I haven't taken a look at mine, but most non-heated O2 sensors are one wire only right? So one wire goes to the ECM, the other to a switched power supply, (Fuel pump power by your suggestion) but what's the other 1 (or 2) for?

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"Racing is life. Everything else is just waiting." - Steve McQueen - LeMans

305 TBI, T-5. 15.4@92 mph
Member Southern California Third Gen F-Bodies

AOL IM: Andy89RS

 

Boy do you have good timing. I just put my heated O2 in yesterday. I bought one for a 92 ZR1, per Mac's suggestions. Installing was a pain in the *** , but more because my wiring harness is falling apart. I wired it to the green wire on the fuel pump relay harness, which was a mistake. That's the line from the ECM that feeds the relay coil. I was reminded by somebody that the ECM feeds that line through an output transister, which is current-limited. Feeling lucky that I didn't fry the ECM, I swapped it to the big tan wire (terminal A) which is the output of the relay and is perfectly capable of dealing with the additional current draw.

After I hooked it up for the first time, I threw a code 32 (egr) and a 54 (low fuel pump voltage). I giggled some harnesses and the codes disappeared. I've got to re-wire the fuel pump plug when I get the ambition. I haven't driven the car yet because I developed a lovely transmission fluid leak

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Where are you all getting your heated o2 sensors, after installing my slps i'm thinking i need one. thanks

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1986 Trans Am
305 TPI
"If it's not one thing, it's another!"
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I bought mine at the chevy dealer's parts counter. My cost was about $62, but I think it retails for about $80 or $85. Parts-store brands may be cheaper, but I don't like getting anything other than Delco sensors.

------------------
The IROC Homepage
<A HREF="http://www.rit.edu/~jli4307/camaro" TARGET=_blank>
View the restoration of an 85 IROC</A>
"I didn't know a bored out Ford could go so slow" -Shenandoah