Please help-02 3.4l horrible mpg/ power loss no cel

Only way to test sensors like that and get any useful information is to use an oscilloscope or a scantool with an o-scope function. Take it to a shop that does good diagnostics, have them tell you what's wrong with it, replace it yourself.

OR

Just replace your O2 sensor and MAF.

(It's most likely a bad O2 sensor)

 

I don't see it, maybe I'm blind, is this a 4 or 6 cyl? If it is the 6, use the port for the charcoal canister. It is the large hose on top and to the rear of the intake manifold, about 1/2" downstream from the TB. You will have to limit vacuum leakage while introducing the cleaner. The brake booster hose will only get cleaner to 1 single cylinder, that is a fact not an opinion.
I really don't think this will do anything for your symptoms.

 

6 cylinder. Ya I'm starting to think I jumped a tooth on timing belt. Sure hope I didn't cuz I don't have much time to check it out let alone fix it.

 

Mind expanding on that? Not sure how the booster would only get the chemical to one cylinder. May be something that I am missing.

 

Sure, If I can stop watching your sig vid long enough.

The brake booster vacuum source on the 1st gen V6 is just below the joint of the "upper" and "lower" intake manifolds. From about 8" upstream of this point the intake plenum divides into 6 individual runners, completely separete from each other, other than being "siamesed" in the casting.

 

FWIW this is not a common thing on the 6. Do you know the mileage on the belt? People frequently go way beyond the 90k mile recommended change interval without issue but they do fail. Many factors play a part in the life of a timing belt, tensioners, pulleys, contaminates etc. It is only a 20 minute job to check it out.

 

I agree. I get lost in her eyes. Gorgeous

 

Update- removed front o2 sensor. Idle fluctuation is gone. Power seems to be back but hard to tell if because its extremely loud without that o2 sensor there. So my question now is.... Bad o2 or clogged cat?

 

Got ya. I never really paid attention to where it went on the V6, since my truck is a 2.7L. I see now it goes into the #3 cylinder. Thanks for the info. I had never used that vacuum port for any chemicals on the Tacoma, because I usually use the PCV hose for that, but was curious.

Did you leave the connector plugged in, or removed it totally? Without being able to connect your truck to my computer here, I would say yes, either the sensor, or a plugged cat. Obviously hard to tell if the intake sound is different with such a huge opening in the exhaust now. I would lean towards a cat because a bad sensor would be least likely of a noise. Try installing the sensor, and just leaving it disconnected. Then drive it.

 

The 02 sensor behind the catalytic converter is just looking for clean air. Your cat could be clogged and not doing it's job or your o2 sensor could be bad.

An easy way to test would be the take your sensor out, tie it to the frame rail or some where it'll get clean air. If your problem stops then it's a clogged cat. If the problem persists you might just need a new O2 sensor

 

Tying the post cat sensor to the frame would give it a high oxygen content reading, and should thus set a code P0420 for catalytic converter efficiency. It would not help in diagnosing if his catalytic converter is clogged. The sensor he removed was actually the AF sensor (Similar to an O2 sensor, but NOT interchangeable) which is located BEFORE the catalytic converter.

 

Yes I unplugged the AF sensor completely and removed it. Problem is gone. Going to install sensor but keep unplugged and see what kind of shot happens. Also gonna clean the sensor while its out

 

Sub'd just in case!

 

Where is that o2 sensor located? Sorry if that's a dumb question, but I'm curious about removing mine to see if my shit mileage is related.

 

Climb under your passenger door and look up. 1 is located just past your exhaust manifold before your cataylic converter, the second is located just past the converter. It will be 2 12mm nuts to remove each o2 sensor and 1 clip. Hope that helps!

 

Good to go. If you end up replacing your O2 sensor, make sure to go OEM and not cheap aftermarket China ones.

 

Yes. Looks like Tara Reid's cuter, younger, sister. Put a jolt in my pants.

 

Dude I was seriously think tar Reid's sister also. Yum

 

Tara Reid's sister or Tara Reid herself are the most common beliefs. She's just a regular nutty girl.

 

Cat is 100% clogged. Removed the exhaust piece, poorer water down one end after I did the flash light test. It took the water 1 minute and 12 seconds to make its appearance on the other side of the cataylic converter. I didn't realize how hard it would be to pound that sh** out