I know chevy owners and some ford owners use o2 simulators to take out the sub o2 sensors that check to see if the cats are working, they put in this simulator, take out the cats, and no engine codes or anything. Is there anything like that for the 400 series lexus models? If not any other alternatives?

 

check with this guys. Casperselectronics.com

 

I just purchased mine from Summit. Caspers electronics makes them.

 

Cool, thanks guys.

Did you just get the toyota/subaru one? or better yet which part number did you get? thanks that would help a ton

 

according to Caspers Electronics either part #104037 O2 Sim - Single Retro
Or
Part # 104057 Toyota / Subaru Simulator will work.

I purchased the first one, it is worth my time to soldier a few wires to save $80.00
But Caspers claims either one will work.

104057 is a direct plug in.

 

ahh cool thanks, i did some snooping around, and i called summit. They said the 104057 one had an input from the first o2 sensor and back out to the computer so it will give the computer a signal it can use, and he said the 104037 just sent back a dummy signal to the ecu which could alter a/f ratio. I reall dont want to waste 80$ if i dont have to, but i want to be sure about anything before i do it. Do you have any comments to what the guy told me over the phone?

 

According to Caspers Electronics Tech, they both do the same thing, and you have to have a working O2 with both of them.
The more expensive one has the wiring harness on the O2 Sim, so you just plug it in, inbetween the O2, and harness.

The less expensive one, needs you to cut the wires from the O2, and wire 3 of the 4 wires to it.
one you leave.

They both will send a good signal to the ECU telling it that your cats are working.
The first 2 O2's are the ones that tell the ECU if your running lean, or rich.

 

Ok cool thats what i was hoping. Thanks for responding, i appreciate it

 

If I can revive this thread;
I have bone stock exhaust. I changed my 2 upstream sensors last weekend and the CEL went out for 2 days then came back on. It also leaned the car out (you can tell by the exhaust) and runs better, so I know that helped something.
I'd like to try one of these o2 simulators, but don't want to put good money after bad.
I'm willing to change my downstream sensor if it will resolve the problem, but w\ 105k miles, I'm affraid that my cat may be bad too (though it makes no noise).
What are your thoughts to help me get rid of the infamous CEL? Should I get a simultor, new sensor, or will I need both?
Thanks!

Chris

 

Bump:

I'm out here looking at the exhaust system again in pursuit to rid myself of the infamous CEL.
I have to say, though, I can't find that 3rd O2 sensor ANYWHERE. Does the '94 SC300 have the 3rd? Also, will these simulators work on the '94 (ODB1) cars?
Thanks all!

 

105k? your cat is probably just fine

 

Where in the heck is the O2 sensor on or after my cat?
I'm telling you, I'm looking all over the darn place and just can't find it. I don't even see any wires around there. Is it true that I can just disconnect it and all will be well?
It's a '93 SC300.
Also, I just read that changing the manifold sensors w\ generics is a bad idea, but it's too late (of course). Thoughts?

 

Speedforsale makes them for the Supras, you might look into them.