02 Taco Code Help

Hello all-

Just joined the Taco family with an '02 2.4L Regular Cab 140xxx miles (pics to come).

After replacing the bald tires I am working to clear the codes currently being thrown. I am currently getting both P0110 and P1135, which from what I have read are Intake Air Temperature sensor issues and likely an upstream 02 sensor that needs to be replaced.

Is there any order I should tackle these before just ordering parts willy nilly?

I stopped by a local exhaust place who indicated I should replace the air intake boot first and that may address both issues.

Thanks in advance and look forward to no longer simply lurking!

 

That P1135 likely just means you need a new O2 sensor (upstream). Make sure you get the Denso brand one since that's the brand Toyota uses for these trucks, anything else is a gamble and could make the code stick around.

I don't have any experience with the other code (P0110) sorry

 

I figured that was the case. One f/u question:

What is missing from these Ebay listing that makes the replacement O2 Sensor so much cheaper than RockAuto/Amazon etc.

https://www.ebay.com/itm/DENSO-234-...r-99-02-4Runner-00-03-Tacoma-3-4/392202366198

I see multiple listing that are $30 vs the ~$115.

Thanks for your advice!

 

Do you have a manual or AT trans? This makes a difference as the sensors are different based on trans (has to do with cable length).

Have you tried cleaning your MAF sensor?
I'd start with that for the P0110.

The sensor you linked to I doubt is correct - I'll check in a few and update but upstream would be Air/fuel ratio sensors and AFR sensors are not cheap, especially Denso. That eBay listing is probably a knockoff.

 

There are a lot of knockoff/scam sensors sold on eBay, I wouldn't trust that one personally. When I got my rear o2 one I got it from Pep Boys and it was around 100 bucks

 

Yeah, I paid 118 for mine (3.4L Auto).
Denso 234-9001 Air Fuel Ratio Sensor

$137 Denso 234-9001 Upstream Air Fuel Ratio Oxygen Sensor with 10.6” 4-Wire Harness, for Auto Trans Equipped Vehicles

https://www.amazon.com/dp/B000C5WD2Q/

 

Yep, that is definitely a pricey sensor.

So if you have the 2.4L Manual Trans, you're looking for:
Denso 234-9001 AFR Sensor

$137 Denso 234-9001 Upstream Air Fuel Ratio Oxygen Sensor with 10.6” 4-Wire Harness, for Auto Trans Equipped Vehicles

https://smile.amazon.com/gp/product/B000C5WD2Q

If you have a 2.4L Automatic Trans, you're looking for:
Denso 234-9002 AFR Sensor

$153 Denso 234-9002 Air Fuel Ratio Sensor

https://smile.amazon.com/Denso-234-9002-Fuel-Ratio-Sensor/dp/B000C5YCYS/

Source:
http://densoautoparts.com/find-my-part.aspx


EDIT:

Comparison between the denso sensor and the ebay sensor linked in post#3

ebay Seller lists as 'Unbranded' in the item description. Color is different and auction sensor does not appear to have a gasket.

Actual Denso 234-9001 -



eBay listing:

 

The P0110, imho, is the one I would fix first. The PCM uses the reading from this sensor from cold start, open loop, to running temp, closed loop and it will effect fuel mileage as well as not allow the Smog readiness monitors to run.

The other code is for the heater circuit of the A/F sensor. There are no fuses for the heater circuit on the A/F sensor to check, it is powered off of the EFI relay. This one of those parts you might get lucky with and aftermarket unit. When the truck is first started, battery voltage is supplied to one side of the heater/resistor inside of the A/F Ratio sensor and the other wire goes to the PCM. The PCM is expecting a certain voltage within a certain period of time and if it doesn't "see" it, it trips the CEL. A 1 ohm resistance difference from the factory spec is enough to trip the CEL.

 

I had a feeling that was the case with the O2 sensor. I'll stick with a trusted place to purchase so I can hopefully knock this code out for good. I do have the 2.4L A so the 002 appears to the be the right part after reviewing the Denso website.

Glamisman- What part would I be looking for aftermarket for the P0110 code? From what I read and gathered it looks like the IAT sensor is in the MAF part for model year 2000-2004 so I'm assuming I'd need a whole new MAF if cleaning does not work. I did notice that i have a wire harness unplugged near the MAF under the hood last night, I'll have to snap a picture and attach as well. Initially I thought that the fuse by the MAF was the issue but found/read that is a noise filter of some kind.

 

eeew... yep you are correct. It IS integerated into the MAF. I see aftermarket ones for under $20 and others for over $100, tough call on what to do. This being and "electric" part is probably not returnable if you were to order online. One thing that you might be able to get away with is to take the truck to an O Reillys or autozone or other chain store and see if they will scan it and then they will make a part recommendation. This is where you mention that if the part they recommend does not "fix" the issue right there in the parking lot, will they take it back? Most of the time they just might... kind of a try before you buy. Clear the codes and if this is a success then the same should apply to the A/F sensor. Unplug the old, plug in the new and start the truck momentarily to see if that code clears.

 

I snapped a few pics tonight. Does this all look stock? The plug with the yellow cable is unplugged and sitting on the frame.

Thanks for all your help, it's greatly appreciated!

 

I'm like 99% that yellow cable is your airbag. That definitely does not look stock. Then again, I'm used to the 3.4L

@Empty_Lord (?)

 

the upstream sensor is actually an air/fuel ratio sensor. These are much more expensive than a regular O2 sensor. That's why you see $30 sensors and 100$ sensors. They look identical but they function a bit differently

2000 is when they switched to the air/fuel sensor as the upstream sensor on 1st gens. Before that, both sensors were O2 sensors

Oh and only get Denso, as toyotas are known to be a bit picky with other sensor manufacturers

 

@Area51Runner I don't think it's the airbag cable because I've seen it in other posts (granted they weren't the 2.4L). I can't find a good picture of the 2.4L engine bay searching the forum if anyone can direct me in the right direction to compare against.

https://twstatic.net/attachments/20190606_144901-jpg.3363674/

 

Further f/u, found a picture of the full engine bay from the prior seller.

 

I'm betting that plug near the yellow cord needs to be plugged in, I'm not familiar with the 2.4l but I can't imagine something that big would just be sitting unplugged like that naturally. Is there anything around there it should plug into?

Since it's tied in place the part that plugs in may have fallen down somewhere lower in the engine bay

 

Is it possible I'm missing these parts (circled in yellow). Apologies I'm not sure what they are!

 

That's the ABS module, if your truck doesn't have ABS then it won't be there

In fact that might be why you have an empty plug there, could explain it

 

and below that is cruise control

 

That might explain the mystery plug right there, might just be normal for him