Hi
I am getting a New York state inspection done and I have a check engine light on my wife's 199 4runner sr5 3.4 v6, automatic. First off the technician says I have California emmissions and that sensor I need is special. I checked that out on the board a week or so ago and you good people confirmed that as correct. I need the front sensor which is actually a fuel ratio sensor or something to that effect. He told me the part was $150.00 and that seemed in line with URD prices and they were both Denso parts. He orders it we make an appointment for today and the part doesn't fit. The end where it plugs in is different. He calls the local toyota dealership and they are sending one over but now he is telling me that he can't finish the inspection because the vehicle has to be driven so many mile for two complete cycles to occur. It needs to get to a certain temperature and then cool down and go through again. Is this correct? I thought we had to disconnect the battery and the efi fuse to reset and we would be on our way. Please let me know as my wife is there now disputing this with the owner.
Thanks

 

I'd pull the EFI fuse under the hood and then plug it back it. I think you're referring to the Mass Air Flow (MAF) sensor on the intake? Give it a try. Also have someone take that code off for you.

 

yes it needs to be driven around for the computer to re-learn and adjust the system.

 

Yeah, it sounds like the mechanic is trying to explain the process for the computer to get back into closed loop mode with the new part, shouldn't be a big deal.

 

The reason why the sensor the guy ordered won't fit is because they sent over an O2 sensor instead of a an Air/Fuel sensor like you needed. The $150 was likely about Toyota list price + a small markup for an O2 sensor (list is about $140 for an O2 sensor) so don't be surprised if they come back saying the A/F sensor is going to cost you even more (unless this was some aftermarket brand). Yes, it is also normal that the vehicle needs to be cycled a few times before it can be tested or inspected (I believe it needs 3 cycles before it's ready).

 

Does anyone have the part number for the a/f sensor? Does the 96 4runner 3.4 also have an A/F sensor? I bought an o2 sensor my 4runner and I am in California as well. I just wanted to make sure i have the right part. Thanks.

 

There were no A/F sensors on 4runners until 1999 so you should be fine with the O2 sensor you bought. Just be sure you bought an OEM or Denso brand O2 sensor and not some other manufacturer (esp Bosch).

You can look up the denso P/N for your truck on Gadget's site:
http://www.urdusa.com/product_info.p...s_id=430006000

If you need the OEM Toyota P/N just call the dealer up and give them your VIN and they'll tell you the correct front and rear P/N's for your truck.

 

Cool, thanks. I bought a Toyota O2 sensor.