What is the trick to get the connector apart? I can see on the new sensor there is a small stop/lock that latches into the female connector. But I couldn't get the little tab on the female connector to release the male connector. Are the connectors so tight you just have to fight it?

Bearbrew

 

Ahhhhh...you need to practice more Kung-Fu grip..

If it still won't come loose.
I usually pry the inner tab with a pocket screwdriver. Then pull them apart.

 

What Nad said- I fought that bugger on my DIL's Rx and decided I wouldn't ever do it again without finding a better way. As Nad said, those that have kept the language filter most under control are those that have wedged a pocket screw driver in the latch to keep it open and then gone underneath and pulled on the sensor wire bundle. You can only get one hand up there at a time, so it takes resorting to trickery!

 

It is possibel to check the MAF sensor with a ohm meter same goes for the a/f sensor in case ure in doubt which one is faulty ...i dont recall the specs exactly but im sure u can find them in the forum if u dig a bit

 

The darn lock on the A/F sensor connector worked the opposite of what I thought it should. I was able to squeeze the snot out of the latch tab and wiggle the connector apart. A 7/8" open end wrench and a dead blow hammer to tap the wrench and I had everything under control. I did displace the large wire bundle just above the A/F connector for easier access. All in all it took about 30 or so minutes to replace. Then another 30 minutes fooling around with my new Autel OBDll reader to clear the codes. Now I will see if the sensor replacement makes any difference.

Bearbrew

 

You had better luck than me. The threads were destroyed when removing the old A/F sensor, now I have re thread with a tap.

 

An hour or so before I tried to break the sensor loose I sprayed the manifold/sensor area down with Kroil, www.kanolabs.com. When I went to remove the sensor I lightly tapped the wrench and the sensor was free. I was able to remove the sensor by hand after it was just barely loose.
There are a lot of different penetrants out there, I just happen to like and use Kroil.

Bearbrew

 

Yeah I forgot to soak it in PB Blaster before. I did spray it after I got it loose. I had to use a breaker bar though and the manifold threads were "stuck" on the a/f sensor. I just re threaded yesterday. Besides from the residual smoke from PB blaster, the check engine light is off and the car runs normal. I just have to check my codes again and make sure everything is cleared.

 

Soaking in oil penetrant overnight works! And, warm it up a little bit just before you start opening the AF sensor, ie. run the car for two minutes, turn off, and wait couple of minutes to cool a little bit. I also tap on it first by holding a ratchet extension against the base of the AF sensor and striking the extension with a hammer 3-5 blows. It opens like a charm using an AF sensor socket wrench. I've had my lessons before when I damaged a frozen sensor on my SC430 by not doing any of the things I mentioned above. I have replaced a lot of sensors since then and they've been all easy (unless I just lucked out haha).

I've also read somewhere that the best penetrant in a is a 50-50 mixture of ATF oil and acetone. In the rankings after they did tests, Kano Kroil came up second, PB third, and WD40 last.

 

Interesting information about ATF and acetone. A couple of projects in the past have required over a pint of penetrant to accomplish the job. It may be a toss-up for cost after purchasing the required components.
Bear

 

After replacing my bank 2 sensor 1 and MAF I am getting these codes P0171 (system too lean), P0300 (random multiple cylinder misfire detected), P0301 (cylinder 1 misfire detected), P0303 (cylinder 3 misfire detected), P0305 (cylinder 5 misfire detected).

What do I do now?

 

How's the vehicle feeling at this point, any hesitation at all?

 

i just did this on my 2001 rx300 i did the fromt a/f sensor by radiator(that was cake) the one under the car on pass side was easy to remove but unplugging the plug with 1 hand is a pain but be patient youll get then clean maf with crc maf cleaner make sur you spray up inside as this is where the wires are. it runs great now. denso sensors on amazon 127.00 denso number 234-9009 awesome prices. get the universal oxy sensor removal tool kit while your there its in red box great tool for all cars. youll be glad you did this. maf usually doesnt go bad just dirty so dont waste money. ygood luck

 

Yes there is hesitation when I accelerate.

 

Is the check engine light flashing?