Acceptable Number of Misfires?

Is this count on the tuned or the stock?

 

If you see high knock (like 50 , 100+) occurring at high RPM then thats not healthy. Low RPM knock is usually noise and typically harmless unless load is part of the equation. There is no way to get rid of all knock if the sensitivity is set to high no matter the octane typically. Cliff notes - low knock count and low rpm is nothing to be concerned about here.

 

Stock

 

Fuel pump recall? Too high for the stock.

 

Why do you say that? We have a few other people in this thread saying it's normal, and a couple of others have seen the same on their stock trucks. I've also seen the numbers remain about the same between tuned and stock on my truck.

 

No misfires on my vehicle that i can tell. Its very quiet, and smooth when at idle. Never ran anything but 87 e10 in it. Only have a bit over 3600 miles on it.

 

B04 calibration on my truck was within 0 to 10 range. I have been monitoring this stuff before I used the tune. And once you start paying attention, you will be able to tell if the engine had a misfire.
Techstream is a good tool to start logging the data. Pay attention to startup, slow driving on the cold engine and under the load.
You mentioned rough running. I would look into crank position sensor, fuel pump recall, running a compression check, check all connector under the hood.
Have you tried the last 2.0 release?actually it fixed all mf issues and even improved the stock #s for me.

 

Check your plugs.

 

The tech stream was counting misfires, but just like you, I could never actually feel them. This is what I meant to say

 

What's your educated and informed response then? You call BS, but provide absolutely ZERO helpful or constructive/knowledge based input.



With that aside, Our trucks seem to misfire from the factory, I'm not sure we've been able to zero in on WHY it happens. Given that Toyota allows so many misfires without a CEL, I'm betting it has something to do with the underlying base tuning and Toyota software... They probably (my opinion) didn't want their Tacoma's to run as smooth as Lexus.

 

...and yet you provide none.
Trust me. I know what I'm talking about

 

not sure why with so few miles that U wouldnt present this to a dealer & hopefully a good mechanic

has ANYONE done ANY engine modifications at All?!?!?!?!
sometimes aftermarket ' Tuning ' which actaully overides OEM tuning tho it DOES NOT Eliminate
OEM tuning can Corrrupt the ECM

no less iv read this thread several times..............not sure what a' misfire ' is as U describe it
Uv had hundreds ........how did U first notice them
hi way ???? driving under load........idle

many have mentioned a dozen different scenarios & made good suggestions

the gas U use would have to be throw away gas & used recurrently...............i dont think ' octane ' is the source
if the overall timing was OFF so far a misfire could occur..........no less someone mentioned ' crank sensor '

a bad/defective injector in a cylinder could cause a ' misfire '
injecting at rhe wrong time dribbling fuel or Not injecting sufficient fuel

a defective ' coil pack ' could easily present a ' misfire '
firing weakly ........ erratic at the wrong time

the fancy electronic monitor interface is not going to indicate whats wrong
codes sometimes get U in the right zip code

otherwise there are incidental physical apparatus that need investigation

 

+1, apparently it's a thing on these trucks lately. And I like this guy's low-key wisdom delivery after a thread full of noise

Not to ruin anyone's panic, but there are situations where the ecm will show misfires and they never really occurred. The same with knock counters.

Direct injection engines skip way more than people realize, especially on cold starts. That's one main reason our trucks have both. (And emissions, and performance via DI accuracy and you can't very well do port injection if you shove air back up the intake as part of the atkinson cycle.)

Now, for OP, you say your truck "runs rough", well is it dead-skip rough? Don't know? Unplug a coil, you'll know and have a comparison. Alright, now that you have that sorted out, if the answer is "no, not like that" then pay less (less but not zero) attention to the counter. It looked to be more with one cylinder. The usual coil and plug swapping is in order. If you've done all that, nothing found and its still running rough, maybe the vvt is off a bit for any number of reasons. The demon I just found in my wife's crosstrek regarding its rough, hot, in-gear idle was oil contamination in the exhaust cam phaser connector causing it to short the signal a bit and the cam wouldn't move quite as much to match the tune for the immediate conditions. $50 part, redesigned so they won't weep oil, two 12mm bolts to change. Ain't that some shit? It drove us nuts for 15,000mi.

My silverado did the same thing with the misfire counters, I got concerned when I first saw it too. Then I noticed it would happen on decels, when the injectors weren't firing. Ah ha, that makes sense. So if you're going to keep watching the monitors, watch when it happens or start plotting a few things like load, timing advance, throttle position and MAF g/sec or MAP pressure along with torque converter lockout condition and you'll start to see patterns.

My taco has a less-than-perfect idle at times, the injector cleaning cycle has a little to do with that i think but I'll very happily deal with it to never have to deal with the typical DI demons.

Why did I explain all that? To calm you down.

 

This engine is not DI engine.. it runs10% on DI. If...

 

I have yet to see my engine misfire, granted last time I cleared DTC’s was 164 miles ago, but even before that, I don’t remember ever seeing any. Not sure why these things vary so much

 

Not all misfires are detectable by the ol ass-o-meter. Different “class” of misfire. i agree with the above posts regarding further exploration

 

a- ' misfire '

b- ' Detonation '

c- ' Knock '

are three very different cylinder malfunctions

same cylinder some o the time???

different cylinder some o the time

at speed or under load

all three are caused by very different factors whether U electronically monitor or not

 

Whats the best way to log without OVtune?

 

Does it even work? last time I checked it is not on the list of the parameters provided by.......
20 bucks.
10 for adapter, 10 for Toyota PIDs.