I got a code the other day, it is a code 45, "O2 Rich" and the car really runs like a$$, Until the light come on. Is that weird or is it just me?? i have a 93z with a six speed manual. I only have 40000 miles on the car, so could it be a 02 sensor going bad or do i have different problems?? please someone help me out here.

Thanx
Dan

 

According to my shop manual it says to check things like disconnect the MAF and see if condition goes away. Check for a leaking diaphragm in the fuel pressure regulator. check the TPS through the full movement. Check the EGR for sticking, it can give a rich indication. Check the EVAP canister for saturation. check the fuel pressure to be sure it isn't too high (goes along with the diaphragm check).

Last is the O2's and then injectors being stuck partly open. The checks are easy and low or no cost. Do those first obviously.

If you get to having to replace the o2's only get OEM. My truck for example will not run on aftermarket o2's. Believe me I tried to save money that way and got burned for $50.00.

Good luck post if you need more help

 

DTC 45 if for Bank 1/drivers side O2 sensor. If you could do a scan, and look at the long term fuel corrections, it would show you if it is only a problem on the drivers side, or if the Bank 2/passenger side long term corrections are approaching the level where they too will trigger the code for Bank 2. This will tell you whether you have a problem that is affecting both sides (e.g., as mentioned above - high fuel pressure, leaking FPR diaphragm), or a problem that is only affecting one side (e.g. - leaking injectors, faulty sensor).

You could also switch the O2 sensors from side-to-side, and see if the problem follows the sensor = faulty sensor, or if the problem stays on the same side = something affecting only that side, and not the sensor.

OF course you aren't going to unplug your MAF, since you don't have one..... .

 

thanx everyone, that should help me out. So it is normal when the car runs like a$$, but as soon as the SES light comes on it runs fine?? that is whats bothering me right now!!

Thanx
Dan

 

It means something in the "normal" control scheme isn't working, and the PCM defaults to another system that provides better results. A faulty MAP sensor or IAT sensor will play havoc with the speed-density 93's. It can't calculate air density correctly, so it makes assumptions.

Find the problem, because the "default" control will be inferior to a correctly functioning "normal" control.

Not sure if its clear what I mean here....

 

OH! that is what i thought it was doing, but i know it is coming off of the driver side bank. I was wandering if the 160 degree thermo in a stock car would make the car do that at all?? Also someone was saying it was a faulty fuel injector on the driver side, i think that would be the problem??

Thanks much
Dan