Acceptable Number of Misfires?

Which software? Adapter?

 

I use the shot glass method on the motor like seen in those car commercials. I would think if misfires it'd be shaking pretty good. Its not...glass is pretty steady. I would say its every bit as good as my old 4.7 v8 tundra.

 

It's definitely not like a dead-skip or a shut down cylinder. I've experienced that on my last car and it was way worse - not even the same ballpark really. This occurs under moderate acceleration, around 4k RPM. Even though I've got my foot in it, it feels like someone quickly took their foot off the gas then put it back down, like a single "bucking" feeling. That's why I hooked up the scan gauge to look at the monitors and built a dashboard - it definitely misfires right when I feel that bucking.

I definitely appreciate it! Thank you.

Also, a couple of folks have asked me why I don't take it to the dealer - it's not throwing a check engine light, I'm seeing the misfires on a scangauge. I'm not sure if you've ever taken a car to a dealership for an ambiguous or intermittent issue, but 90% of the time it's a waste of everyone's time and nothing gets resolved.

Based on the evidence that I've seen posted here this really isn't an issue, so I'm going to just try and forget about it. Thanks everyone who posted for helping!

 

I provided an opinion that probably is just that, an opinion. But I also stated that toyota obviously knows this truck misfires, hence the generous buffer zones it offers before a CEL lights up.

 

Cool screen shot bruh... Perhaps next time do it without the volume strip across the top and act like you've done it before...

How about an explanation of said screen shot since you seem to "know what you are talking about?"

Or perhaps I should get the therapy doll out and ask you to show us where OVT touched you?

 

I hooked my truck up to techstream after I replaced my spark plugs at 60k. I noticed a couple miss fires were logged. I shrugged, cleared them and never checked again. That was 50k ago, never noticed the misses before, and haven't noticed any misses after

 

That sounds just like my old 93 toyota 4wd pickup 3.0 v6. It was caused when the EGR valve was hooked up. When blocked off it went away.

 

Well, I'm scheduling a visit to the dealership, the misfire has gotten a lot worse. It's still not throwing a code, but you can feel the truck hesitating badly and then bucking a bit when it happens. I was going to pull the plugs myself but fuck it, the truck still has a touch more than 20k miles and is under warranty.

I've been logging with OBDLink and found that 90% of them occur between 3k and 3.5k RPM, and between 30%-60% relative throttle. The Bank 1 short-term fuel trim tends to shoot up to +10-12% when the truck starts misfiring, bank 2 stays the same. And the long term trims are typically -2% and -5% respectively.

I just did an 8 minute round trip to Dunkin after the truck had already been warmed up, and it was driving like absolute shit, tons of hesitation and bucking, and had 36 misfires in that brief jaunt. That was enough to convince me that there's more going on, and it now seems to be regular enough that I'll be able to replicate the hesitation and bucking for the service tech.

Still completely stock engine and tune, still running 93 octane from Irving or Shell at each fill-up, still getting the misfires spread across all 6 cylinders pretty evenly. I tried going down to 87 for a couple of tanks too, no difference.

Wish me luck.

 

That sounds like a good plan. Something is definitely not right.

 

Dealership found the issue, I'm really pleasantly surprised. Bad gasket on the intake manifold. I never thought that they'd take the time to chase down an intermittent misfire that wasn't throwing a check engine light, maybe I'm jaded because of my past bad experiences with the BMW dealerships here in CT haha.

 

if an owner is concerned then tracing actual culprit o misfiring is the only way to go

i read 1 situation whereby 1 owner put in new spark plugs

did NOT check gap assuming set at factory

cant blame that on toyota or the dealer

no less it must be considered where & how misfires are occurring

they happened with carburetors distributor caps points etc

at idle a direct result of stringent EPA requirements the engines are cut back drastically

idling in gear warmed up from 550 rpm to near 1000

my prev prerunner / rav4 idled at a flat 600rpm........................

fuel ratios are cut back drastically

air is stumbling thru the intakes resulting in idles being raised contributing to misfires / rough idles

 

Kudos to that dealer for actually doing their job and identifying the issue. Would you mind naming them so others in the area know there is a shop that is willing to do what they are supposed to?

I too am jaded in regard to dealers. If it's not warranty work (that I have already mostly diagnosed myself), my vehicles never see the dealer shop after I drive them off the lot.

 

This was Lynch Toyota in Manchester, I definitely like the service manager there. When I bought the truck and was concerned about the driveline vibration when taking off hard from a stop, he gave me a pretty good lesson on what axle wrap is and why it's happening, showed me the same behavior on another truck, etc.

 

Nice, good to know. They were good to work with when something decided to make lunch of the knock sensor wiring harness on my '14. They handled all the insurance from start to finish and got it taken care of quickly.

I was less than impressed with their sales team when I was shopping for my 3rd gen. I barely got a hello from any of the 5 salesman that were standing together bullshitting when I walked in. When they realized they couldn't convince me to buy an auto they wanted nothing to do with me.

 

I actually bought mine in White River Junction, VT. I could not find one the way that I wanted it around here, and the local dealerships had absolutely zero interest in doing a dealer swap or a custom build for me. Coming from mostly German cars, custom builds are extremely common so I didn't get the lack of interest in helping me. Either way, I really liked that dealership in Vermont, they gave me a killer deal, with no bullshit on my trade in.

My buddy just did a custom order an a 2020 Tacoma though, he was having the same problem until he talked to Hoffman in Avon, he said they were awesome to work with on the sales side. Keeping that in my knowledge bank for the next time I need to buy one lol.

 

I thought this might help other folks that havent solved their misfiring issues, I've been hunting a misfiring issue P0303/05 that started in sept and couldn't figure out after replacing the recalled fuel pump/plugs/coil. Today the dealer found this exact issue here

https://www.tacomaworld.com/threads/2016-tacoma-in-limp-mode-fixed.659782/page-3

 

Thanks for sharing this!