Steering/floor vibes? Clean your MAF

Yeah that's the part that kind of puzzles me as well... I've been through mud a couple of times but most of what I've done are rocky forest roads. And my original OEM filter isn't too dirty so that's the only thing I can think is assembly residue

 

I have felt the same issues you have for 18k miles...

I have the TRD Air filter which I try to clean every oil change but its next to impossible to get it totally clean. I will have to take a look at the MAF as well...

no power... rough shifting and idle. feeling the road in the wheel sometimes. and the worst gas mileage ever...

I think Im going to go with a new paper filter and clean the MAF to see what happens.

There is a recall for the CPS coming out too? for like 35k trucks? they will release the recall in july is what Ive heard. I have been checking the recall page from toyota daily and it only shows my rear diff recall as of now

 

Yeah, the MAF really was pretty simple to clean. But it definitely changed the behavior which I could see very clearly in the O2 sensors and fuel trim numbers. Before cleaning, readings were all over the place, but in general readings were lean but sometimes went far too rich. Best correlation I can see in the data is that when coasting / cruising, the fuel trims quickly correct to near 0 and O2 sensors remained in the 3.2ish range unless immediately after accel / decel and then immediately reconnected to what the manual considers normal. Put the foot on the gas now and it GOES. Really does make me wonder whether theres some intake leak or something on these b/c if a lot of the lugging people experience is due to poor fuel / air management there may be a lot more folks with this issue who are simply complaining of the poor power on the truck...

 

Im all for a 5 dollar fix with can of MAF cleaner

 

This is very interesting! Good work OP!

Did you remove the MAF to clean it or just spray it while still in the intake??

 

Removed it. Pretty simple just be careful. There is a clip that holds the connector on, just barely lift it at the bottom and it will pull out pretty easily. 2 philips #2 screws hold it in, turn counter-clockwise (facing the front of truck). I don't think cleaning it while on the intake would be wise b/c you really need to douse it real good to get any debris to properly drain off. Also, I didn't just clean the wire, I sprayed down all of the air tunnels and even the connectors.

 

I am curious how many of the people this helped are running oiled filters?

 

Not I - all OEM paper....

 

The fact that OP has the OEM filter combined with relatively low miles makes me think it's assembly oil from the factory. However, I have the trd oiled filter, and will be going back to paper. At their very best the oiled filters do nothing, and at their worst they mess with your MAF. Lose/lose.

 

just picked up my paper filter and gonna clean today... Ill update as well.. keeping my oiled filter but running the test to see results

 

Did you unplug the battery either during or after the cleaning? I remember having to unplug the battery when I did my 4Runner to reset everything afterwards.

 

Gotta put this on the list of things to buy as soon as I get home.

 

Just thinking out loud here and I could be way off but what if the CPS is failing and causing the missfire which could be a backfire through the intake and that is what has or is contaminating your MAF?

 

Very possible... wish there were an easy way to test the CPS. Because I'm equally puzzled by how my MAF could have gotten dirty with a clean OEM filter with 12,000 miles on it.

 

I did not disconnect the negative battery cable this time, but the day prior I did disconnect the battery cable for a few minutes. In my experience, disconnecting for ~10 mins or so is plenty to reset the learning as verified by the data. Only reason I didn't this time was because in reading the "replacement" instructions for the MAF it didn't indicate a disconnect was necessary so long as the ignition is off. I also didn't do it b/c I wanted a very clear before/after assessment that included a single variable.

 

So I went ahead and replaced my oiled trd filter with oem paper, cleaned MAF, and reset short term learning yesterday. The engine air intake box was a little dirtier than I expected. I cleaned everything really well, let it sit for about 45 minutes and then reinstalled.

First impressions yesterday were not as great as I had hoped for. Subjectively the truck started way smoother, but then immediately felt the buzzing during idle. Anyway despite an improved throttle response around town, I was getting like 13-14 mpg yesterday for about 15 miles of driving.

Drove about another 25 miles today only to have things improve. Vibes have gotten much much less noticeable. Was getting pretty poor gas mileage again this morning, like 17 highway, but felt the truck adapting and smoothing out.

And then the last leg of my trip was 10 miles back to the house, almost got my PB fuel economy. Ill give it a week to settle in and report back.

 

Thanks for posting your results! Cleaning the MAF definitely made a difference in my case. After another 100 or so miles of driving over the weekend, here's what I'm seeing:

-steering vibes are back, not as noticeable or annoying as before I cleaned but seems to be slowly inching up, especially noticeable at highway speeds like it slowly relearns to vibe the engine more and/or lacks in power to Lee the power steering pressure up. When it runs well, I feel nothing in the steering wheel hardly at all except the faintest in the 2k range
-fuel trims and O2 sensors seem to be remaining in the range I'd expect, generally sticking around 0% or 3.2-3
with jumps in either direction after acceleration or on deceleration.
-sulphur smell has not returned although I am concerned about whether any damage was done to my cat...
-data logs are still somewhat troublesome as I am still recording an All Cylinder Misfire normally when in injection mode 2 on heavy acceleration such as merging or turning into fast moving traffic. Sometimes it shows a cylinder (have seen either 1, 3, or 4) but most times it's just showing I had a misfire in the all cylinder data point
-mpgs have remained at a pretty stead 18 or so... I have NEVER seen over 20 in this truck... sometimes I could get 21 on a trip when I ran e-free but nothing close to what I see in yours and I can't imagine the rolling hills of middle Tennessee would be much harder on fuel than your neck of the woods up in the PNW

We'll see how it plays out, I may change the spark plugs just for the hell of it and may even do a CPS swap at some stage. Would be interested to see if anyone has a good way to test the injectors?

Perhaps it will continue to get better -
DefInitely Is breathing better and has more oomph, but I'd be lying if I didn't say I continue to worry that all my efforts to reset learning, clean MAF, and many other things may just be the treatment of a symptom caused by another larger issue which eventually causes the symptoms to resurface. And since I have no one I can count on from Yota to even validate or help, I'll either keep on trying or get rid of it. I'm hoping not the later.
Time will tell

If anyone else out there has an OBD adapter and an app that logs data, I'd love to see some comparisons around RPMs, torque, power, misfires, O2 sensor voltage, short and long FT (b1
And 2), MAF, intake manifold pressure, and high/low pressure fuel injector readings. The service manual gives some ranges for diagnostic but most are readings taken while idle or P. Not real driving

 

What data logger are you using to capture all this data?

 

I don't know what a MAF is. Please explain what it is and where it is. Sorry to be stupid but I need to learn.

 

I'm just using the Carista OBD adapter connected via bluetooth to OBD Fusion on my iPhone