Hesitation during low RPM acceleration

I'm with you, julman99 and Firn. I even had a first gen Honda S2000 that had it's peak power at over 8000rpms. It was relatively gutless below 6000rpms, but it was silky smooth. In my 40+ years of driving, I have only owned two automatic vehicles, and have not experienced an engine that runs this weird. Either ours are anomalies, or others are not as sensitive to the issue. I believe it is the former, and just want to know what is causing it.

 

I should mention that one of the 6 speed trucks I test drove at the dealer, hesitated really bad. I chalked it up to being low on fuel and perhaps having a little moisture in the tank. When I drove the truck I bought, I didn't notice the hesitation at all initially. It seemed to pop up after 500 miles or so, but still isn't as bad as that first truck I drove. If I reset the learned values in the ECU, it seems to drive much better but then eventually reverts back to the weirdness.

 

I had been bs-ing with a friend from n.h. this morning that's buddies with a tech at a toyota dealership up there. I mentioned some of the weird stuff guys have claimed here. He told me there's a lot of truth to it, saying some tacoma's like any cars, or trucks, you can get one that runs strong, and others are a turd. They can't explain, or have found a reason yet, only that it happens.

 

Looks like you have access to techstream or vf.
Have you tried to datalog the issue?

 

Yes - I have VF Tuner. I haven't tried to datalog the issue, but it is on my list of things to do. I am by no means a pro at using that.

 

Is there a "How To" for data logging with VF Tuner or any suggestions as to what parameters to monitor in order to narrow down where the hesitation is coming from and how to flag time stamps in the data when a hesitation event happens?

 

vF is somewhat limited on what you can log, so here are some instructions with techstream, if you have it:
https://www.tacomaworld.com/threads...ine-ecu-reflash.515734/page-165#post-17378987

Here are some (old) vF Tuner logger instructions as well:
https://www.tacomaworld.com/threads...n-turbo-systems.566390/page-513#post-24599155

 

Has anyone who feels they have this issue checked to see if their spark plugs are tight?

This is just such a weird issue and does not happen to all vehicles. With the multiple reports of blowby on lose plugs from the factory I have to wonder if its related.

I only checked two of mine (the easy ones) which were fine, but want to get to checking all 6.

That said,
I have been doing a little bit of logging/monitoring and will say that I notice it more when under moderate load and fueling is maintaining its normal 13.8-14.1 AFR range, its hard to say but I feel like it gets a little better when the AFR starts to get more rich. At lower RPMs, say below 3000, it does take a fair bit of time at WOT before I see the AFR start to drop from the normal ~14. None of this is normal driving however as I don't ever got WOT in say 6th at 60 except to test this.

 

Thanks. Unfortunately, I don't have Techstream. I will try to log some data in the next few days.

 

Yes - I did check the torque on my spark plugs and all seemed fine. I was hoping it would be that easy!

 

I found something and created a different thread: https://www.tacomaworld.com/threads/acis-tuning.801256/

You may want to try disconnecting ACIS to confirm that is your issue, for me the engine feels buttery smooth without ACIS connected, however it looses a lot of top end power. Follow that thread for updates on the manner.

Cheers!

 

I ran without my acis for some time and still had the same issues. The severity was possibly reduced but the issue was still there. I did not notice a lack of top end however

 

@Toy_Runner

Fysa

 

I cleaned my throttle body today with some elbow grease and it cleared up any stumbling i had under moderate load

 

How many miles on your truck,and how dirty was it?

 

114'000kms roughly and honestly not as bad as I expected since it's my first cleaning but took care of the stumble and increased my throttle response. Haven't done plugs yet nor checked plug torque ever

 

I have this same issue, I tried running a tank of premium fuel this week and it's almost resolved the issue.