HELP!!!!!!Front O2 Sensor and Knock Sensor Problems

[PsyckoDrifter]

Hey guys, I drive a 93 240SX Fastback SE with 113k on chasis and a new KA with estimated 85k on it. My car has been having problems running smooth. On a cold start my car flies. It cant get traction, but once it warms up to normal running temperature, it seems like the car just doesnt want to move. When I level off in 1st gear the car feels like its sputtering and dying. The only time it doesnt do that is when i either launch the car, or burn the f*** out of the clutch. I ran a diagnostic on the ECU because my check engine light was on and it gave me a code 33 and 34, which are the front O2 sensor and the Knock sensor. I was just wondering if either of these could be the cause. If not, what can it be? And what problems CAN these 2 cause? All help is greatly appreciated. Thank you in advance.

[PsyckoDrifter]

Oh and my car feels like it has no torque at all. All throughout the RPM's i feel like i have the same power.

[r3v_v3ng3]

have you tried replacing the sensors?

[PsyckoDrifter]

have you tried replacing the sensors?

not yet. but will just replacing the sensors solve my problem?

[zachattack_5491]

Do the O2 sensor first. That'll cost you like 20 bucks, and it sounds like that would be the problem. I've had many o2 problems. If that doesn't fix it, I highly doubt the knock sensor is the problem. And that bad boy is a lot more expensive. Unless of course the knock sensor sensing rod knock... which is bad lol. I haven't had my knock sensor plugged in since I bought my car. Is doesn't make a difference.

[PsyckoDrifter]

Oh guys I totally forgot to mention, I have a pretty bad exhaust leak. It's almost straight headers lol. I feel like a dumbass for not mentioning it earlier. I have to say though I've had an exhaust leak since I first got my car back and this problem just started happening recently.

[OutToWinPAHC]

If the 02 is off, the car will run rich or lean. Running with the wrong AFR can cause an increase in knocks emmisions.

I second the 02 sensor, then see how it feels after clearing codes.

[sx moneypit]

Are you talking about nox(nitrogen oxides) emissions, or the fact that if is running lean it will cause spark knock? The exhaust leak will also screw up the 02 readings.

[PsyckoDrifter]

Are you talking about nox(nitrogen oxides) emissions, or the fact that if is running lean it will cause spark knock? The exhaust leak will also screw up the 02 readings.

The exhaust leak will for sure throw off the O2 readings. But, will it make my car insanely slow?

[sx moneypit]

Should not affect the power that bad.

[OutToWinPAHC]

The leak, not too bad, but a a bad 02 will cause power issue for sure.

[PsyckoDrifter]

Thanks guys! I get paid today so the first thing im gonna do is get that O2 sensor fixed. I'll let you guys know what happens. Any suggestions on where to get it from and what brand if there are different brands? I live in SoCal. You guys are awesome by the way. I dont know what I'd do without NICO.

[sx moneypit]

If i was going aftermarket i would get a Bosch brand. If not i would go with Nissan .

[PsyckoDrifter]

I'm sure if I got to the dealer its gonna cost me an arm and a leg so im thinking aftermarket.

[r3v_v3ng3]

my 91 has a 1 wire o2 sensor and they are around $20 for a bosch universal one

[compactfean]

I would go uni three wire! If you do the conversion you will get better gas mileage and faster warm ups.especially in the winter.hit me up if you need a guide for that converion.I got 4 miles per gallon in town! ( didn't change highway gas mileage by much)

[PsyckoDrifter]

I would go uni three wire! If you do the conversion you will get better gas mileage and faster warm ups.especially in the winter.hit me up if you need a guide for that converion.I got 4 miles per gallon in town! ( didn't change highway gas mileage by much)

Now you got me curious. How do you do that and how much does it cost?

[compactfean]

Get a three wire uni drop it in, hook the ground to the chassis, hook the signal wire to your one wire input (stock wire o2 signal) and power wire up to 12v source that is hot only when engine is running. If you can't find one splice into the 12v wire from the alternator. I saw a three wire uni on ebay 20bucks free shipping. If I'm not mistaken newer 240's come with a three wire.

[compactfean]

I'd definitely stick with name brand. Though just for piece of mind