miataspeed1point6

iTrader: (1)

I've been reading alot about widebands lately. I obviously cannot afford one, but I did hear of people swapping to a 4 wire 02. Why? I searched around but could not find much info.

From what I understood they are heated to produce a better reading? Is there any reason I should go rip out my single wire (93 1.6) and replace it with a 4 wire? Thanks for any help.

Edit: the title should be 1 or 4....dunno where I got 2?

mschlang

A heated O2 will come up to temp sooner than a non-heated sensor. I don't know exactly how the stock ecu does it, but most likely it ignores the O2 until coolant temp is up. Since the ecu is going to ignore it anyway, I doubt it would do you any good.

bripab007

The 4-wire will heat up faster and help your ECU get out of super-rich cold-start mode (helps if you've ever moved your O2 further downstream of the combustion chamber, like some of us), plus it is better grounded, so it may give a slightly more accurate signal.

No reason to rip your 1-wire out if it's working alright, but, at ~$35, no reason not to buy a 4-wire when yours needs replacing.

miataspeed1point6

iTrader: (1)

Sounds logical. Thanks for the info. I'm not sure if mine will be due for replacement anytime soon, but when it is I'll swap over.

mschlang

Cold start enrichment is decided by the coolant temp, not the o2 signal. While a heated sensor will help if it is moved from the stock location (due to the sensor not cooling off at idle), it will still be ignored until the coolant temp comes up.

bripab007

You're absolutely right, Mike, I totally forgot about that. However, my other statement that it'll give a more steady signal during low-load situations, especially if you've moved the sensor downstream holds true.

mschlang

For sure. On my mustang, due to the longtube headers, single wire sensors are totally unresponsive unless there is a load on the motor. Perfect application for a heated sensor.