Slight miss?

Has anyone ever felt what feels like an intermittent engine miss in your trucks? Thought it was just me, but my daughter drove my truck last night and mentioned it also, V-6 auto.

 

If the A/C was on it could just be the compressor cycling on and off.

 

Think I might have noticed that in mine a couple of times while setting still talking to someone while it was running. It could have been the A/C compressor cycling as just mentioned. It happened for a split second just enough for you to say what then it was gone.

 

Torque converter lock up at slow speeds. Causes engine to chug

 

Yes. Mine does it too. I have the manual and it really only happens when the A/C is on. It's not that the compressor kicks in and I feel it occasionally, it's more like the A/C puts a constant strain on the engine.

I know the feeling you're describing. It's hard to do it just with words.

 

Mine does this too. Around 2300-2600 rpm if in going easy especially. I think it may be the second injectors kicking in but don't know. I have been trying to find another v6 to see if it's normal.

 

All injectors run until 3500ish RPM and then it switches to direct only. Or under WOT

 

Why would they cut back at 3500? I'm barely ever that high in rpm

 

That's how they chose to run it. YouTube "Toyota d4s"

 

It's the ac clutch on mine

 

It is odd. Turned my ac off and don't feel it. And like fdbyrne said, it's not the ac cycling, it just makes it happen for some reason. But does now seem to be connected to the ac system

 

There isn't a magic cut off, but as RPM rises or engine load rises exhaust temps are higher and produce less emissions that cannot be controlled by the catalyst.

The port injection works in tandem with the direct injection simply to produce a specific combustion to help warm the catalyst and allow it to do its job. HC, CO and NOx is the enemy in North America. Exhaust temp control makes all 3 easier for the Catalyst to convert.

Direct injection got rid of air injection pumps and EGR valves, it wasn't introduced for horsepower.

 

Anybody think this is what tey are experiencing?

https://www.tacomaworld.com/threads...-out-in-traffic-on-full-accelleration.448270/

 

I have a manual so thats not my issue. What I am feeling is a very slight stumble or split second drop in power then right back to where it was. Its nearly unnoticeable for me, but is there. Some times it barely does it if at all and other times more often. Its not even a big deal really if it is normal. As far as what those people are experiencing, I have had that happen in other vehicles before. I think it happens when the vehicle is about to shift up and then when you punch it telling it to downshift. Its like its confused for a second as the computer catches up, so instead of doing something, it does nothing

 

At idle? At speed?

 

I wonder if it's related to our junk cam sensors. Mine did it unusually often today and it made me think of the people who had bad cam sensors, just less so

 

This is what happens to me when my automatic shifts to 4th and 5th. Until the RPM's hit 1800ish then I have power again. Worse with the AC on, not as noticeable when it's not on. It's the same feeling you get when you shift manual into too high of a gear and get that lug feeling.

 

+1 on this. The A/C compressor is fucking annoying on these trucks. Not sure why it has to be but it's terrible.

 

My "slight miss" happened a little more noticeably today on a 2 mile drive to from my work to my fathers Toyota shop. Nothing has shown up to this point on the computer but today there is actual misfires read, although no code is present. We have no real clues to what it can be but I do think its crank sensor related since those have known issues. I think the a/c just puts more load on the engine so its felt more

 

This engine just feels like it has zero torque at lower RPM. I have a manual and I have found I'm unable to rely on any sort of acceleration under about 2k RPM.

But I know the engine is there somewhere. Downshift to 4th on the highway getting the RPM's to 3200 and the truck pulls up a steep hill with absolutely no problem.