Steering/floor vibes? Clean your MAF

None of this makes sense - but in reading the article on Lambda (and subsequently paying more attention to the readings) perhaps there is a faulty sensor in the system.

Today was the first time I've recorded a misfire event with 4 occurring concurrently, and this occurred when I had to merge into moving traffic then immediately slow to get around and change lanes. Like an old car I had that would misfire after acceleration when you drop off the throttle completely... system was very rich when this occurred based on sensor data alone - which may be suspect but who knows

 

I've made a thread outlining my shake/vibrations issues with videos to show. I am unsure if I'm having misfires or not but my MPG are quite good (18-20 mixed city hwy & 21-22 hwy). I have not yet cleaned my MAF but will after work today, if something changes I'll be able to tell immediately as my time driving, roads and route is the same each day for work.

Link to my thread: https://www.tacomaworld.com/threads/odd-vibrations-2017-tacoma-trd-sport.496393/

 

Will be interesting to hear your report after MAF cleaning. Especially w/ the A/C situation, there was a night/day response for me when I cleaned the MAF...

 

I tried to keep up with your thread but fell behind. Didn't you report the issues returned after some time? I'm optimistic it's a dirty MAF but with only 2400 miles on the truck it's hard to imagine that's the cause.

 

Wonder if the PCV pressure and gunk might be giving it fits.
Reading around, today's tunes are run right on the edge for economy's sake.

 

I've been getting more vibrations in the steering wheel and pedal lately. Randomly, I filled up with BP 89 octane. I noticed an immediate reduction in vibrations. I also have been averaging 2-3 more miles a gallon with my typical driving patterns and noticed slightly more pep to the engine overall.

Also, I posted a while back about feeling a slight miss. I also feel what I believe my torque converter shuddering.

This evening I cleaned my MAF. I'll see if that has any effects. In the meantime, I'll continue to look at/shop for Tundras.

 

Just cleaned my maf but haven't driven it yet, it looked unlike any other maf I've cleaned. There wasn't a little sensor floating in the middle like most mafs.

Something I did notice when taking the air box cover off to remove the maf was that the worm clamp holding the intake tube to the intake cover was extremely loose, I wonder if my engine was pulling in unregistered air since it was post maf, this would cause a lean condition (too much air, not enough fuel).

I was also shocked to see there is a normal paper air filter on the body-box side but there was also some sort of net/filter built into the air box cover. Have never seen anything like this before.

 

This. I forgot to mention this.

Mine was the exact same way.

 

Well I didn't really notice any change in my driving vibrations/shaking but I really believe mine to be from something in the suspension/steering. I did notice my shake when the A/C kicks on isn't as harsh as it was before and also the truck seems more peppy with less shuddering when trying to get up to speed which is great. MPG's also increased, pulled 21.6mpg on my 20 mile drive to work.

 

After I cleaned my MAF and took a long drive, around 40 miles one way, I got 19.8 with the AC for 90% of the time. Thats been the best average for that type of drive so far.

I am still not getting the 22-24 mpg that some others are getting but, Ill take the 19's over 14/16 any day. On the way back I got 19 with a stop then 18. Both had AC and the traffic was a little different.

My clamp connecting the airbox to the sensor was also so loose it might as well not have been there... I imagine that cleaning and making that tight would do wonders for a truck that was running well.. so I am hoping that as time goes on that my truck will get better and better.

Side note.. Still getting 11/13 mpg in the city on my drives around town to get coffee.

 

Are you driving in "D" or another mode? Have you tried to reset the ecu by pulling the negative on the battery for 10 minutes or so? That gas mileage is extremely low, hell I've gotten almost 11mpg average towing my 4200lbs camper 65mph on the hwy.

 

Interested to see the results here as well... something with the fuel maps are wonky here. I've had multiple cases of simply changing gas brands or octanes immediately removing ALL vibes only to return eventually - many times worse. Finally convinced myself that maybe all my switching was confusing the ECU and am sticking with the same brand and octane. Also I subjectively believe something in the additives used in VPower Shell (which would still be present to a lower extent in the mixed 89) do not agree with this engine.

I've NEVER experienced this with any vehicle I've ever owned. I've always just put gas in from a respected brand and had no issues EVER.

 

I checked the worm screw clamp on my truck. It seemed very loose and I hand tightened it. I haven't bothered to clean the MAF as I only have 1000 miles.

Anyone have a way to find out the torque spec? I agree it seemed useless and like it could leak unfiltered air into the engine.

 

haha... yes in D.

I have reset the ecu by pulling the negative.

The low gas mileage is why im trying to hunt down the problem

 

I'd be looking for a Tundra too if not for all the city driving and parking in tight underground garages. The Tacoma really is the perfect vehicle for me based on capability and size... I'm a weekend adventurer in the mountains who likes to do some mild offloading and lots of forest roads in nat'l forests but needs something practical for DD in the city and the ability to haul lots of gear. Sh.. as much as I hate them, if a Ridgeline wasn't so fugly and was more offroad capable... I can't believe I just said that, but damn these issues are ridiculous

 

Your daily commute is nearly identical to mine with same MPG results, but I'm on Yokohama Geolandars. Same octane fuel rating too! The only thing is, I haven't cleaned any sensors. My tires are set at 34/33 fr/rr.

 

Picked up the truck after being out of town for the last few days and it drove pretty well, and my logs showed it running richer than it has been based on the lambda and fuel trims. First time I have driven it recently with zero misfires... still plan to replace the CPS when I can get a few minutes in a morning when it's cold to check that box. Maybe now I'll get another week or 2 of decent performance at least...

 

First, thanks very much for creating this thread and following up with your detailed findings and data.

I too have been dealing with declining fuel economy (compared to new) and periodic rough idle/ increased off the line "bog". When I read your thread and the other one dealing with loose intake clamps (thanks @mateo_roberto ), I thought - well yah, it's definitely worth a look and a $5.00 can of sensor cleaner!

The skinny before facking with it:

1. Clamps - one nearest MAF was kinda loose, the other tight;

2. Cleanliness of filter/intake tube/MAF - all looked fine to me, no evidence of dust ingress after filter (paper OEM). I will admit it's hard to see anything inside the MAF itself, but if you shine a light in the downstream side of the main bypass port you can see what looks like a metallic surface inside (look through the top or bottom slits);

3. MPGs - Varied between 13.5 and 12.5 l/100km (17 and 18 mpg) on daily work commute unloaded, approx 11km of back road (50-80 km/h) plus 4 km of highway (100-110 km/h) plus 1 km of stop and go city traffic. Several hills. If I really tried hard and great great grannied it (and hit all the lights right with no traffic), I MIGHT see around 11 l/100km (21 mpg). The planets would have to align too. You might say 21 mpg is damn good, but you gotta understand - I used to see better mileage than this every day, just driving normal.

Other variables - The only "mods" I'm running are Duratracs (stock size, standard load), and a Solid fold 2.0 tonneau. I assumed the tires were the most reasonable explanation for decreased fuel economy, due to the much more aggressive tread pattern and slightly increased weight. I also run 91 octane fuel exclusively, since it's the only grade in my area that doesn't contain Ethanol. Some will cry BS, but the "slight misfire" under load is far more pronounced when running lower grades (w/ Ethanol).

The results after cleaning (no battery disconnect):

1. First startup was a bit off, it didn't fire within the normal crank time I'm used to. It was fine after that ;

2. Response off the line (for a 3rd Gen) was better, idle was smooth. I didn't have to be in the gas as much to maintain speed in 5th and 6th gear (manual tranny);

3. MPGs - I ran my work commute so I'd presumably have comparable results, and managed 10.2 l/100 km (that's 23 mpg folks) on the first try. I know I could get it under 10 with near perfect conditions.

I'd say that's a pretty decent result for 5 bucks and 0.5 hrs of work (well, I also had to re-attach an OEM mudflap that I ripped off on the trail recently ).

We'll see if it holds, but for now I'd have to say this is not just a placebo or butt-dyno effect.

Note: It was raining quite hard here today, if that would factor in at all.

Edit: I have the vibes, they haven't changed.

Cheers and thanks again,



Frank

 

It definitely doesn't bog nearly as bad! I drove 350 miles today rountrip to kayak in the mountains. I was heavy on the foot and loaded down getting 19 mpgs. Vibes still present and "not right" but not as unbearable as before and the power feels much better. For now... something is up with these MAFs being able to get mucked up so easily. It makes a difference.

Rough idle is completely gone as well. For now...

 

Even better! This morning I swapped my CPS out for the new one - looked like I did have the old part number on mine. Took about 15 minutes to swap it out. Tight fit for sure but with an angled socket it's not too bad if you turn your wheels to the left.

I also reset the battery as well since I followed the FSM directions for replacement of the CPS.

Instantly felt a smoothness in throttle and especially steering that I haven't felt since I drove it off the lot. Lambda is no longer fluctuating hardly at all either and I got almost 20 MPGs on a 50 miles trip I just took that was a combination of 75-80mph hilly interstate and 10 miles of city driving.

As with anything on this truck, time will tell but initial results are positive between MAF, hose clamp tightening, and CPS replacement. Oddly I'm not even on the recall list for CPS (yet) but it definitely looked like the old part and again - instant change in both steering feel and much better throttle response and instant improvement in MPGs... will analyze for misfires to see if improvements there as well.

NOTE: Harmonic vibes still present but further reduced in intensity since it does feel like somehow the steering is getting more pressure/power.