Anyone else experiencing shift lag during hard acceleration (i.e. flooring it)? My transmission shifts nice and smooth under light and moderate acceleration, but when I really get on it, there is lag between gear shifts. This causes the RPMs to drop more than they should and thus has a significant affect. It's like someone taps on the brake between shifts, which is obviously very irritating. No check engine light. I changed my fluid a few weeks ago and it made a significant improvement with respect to a couple other issues I was having, but I still have the shift lag. I'm wondering if I should pull the solenoids and clean them. Maybe gummed up and/or sticking so they are not engaging as quickly as they should.

 

On the 6AT can only downshift 1 gear at a time in D mode. But in S mode it can go down 2 gears at once. So maybe that's why you see the lag when flooring it. It's probably already at 6th gear and needs to be in 3rd or 4th.

 

The lag I'm referring to isn't when downshifting (although it obviously does this too). I'm referring to lag during upshifts. Honestly, I'm not even sure shift lag is the proper term. It's just not a smooth transition between upshifts when accelerating quickly. For example, the RPMs will get up to 5,000 or so and it will be pulling like a rocket, then it upshifts, the RPMs drop to about 3,500 and it doesn't pull very hard again until 4,500. It's the decrease in the rate of acceleration after upshifting which is the issue. It makes sense from a logical standpoint (higher RPM = quicker rate of acceleration), but it doesn't seem normal. It should pull hard and accelerate consistently when the RPMs are this high. I'm not sure if it's engine related or transmission related at this point. With no check engine light, I'm just guessing, which can get expensive. I can't help but wonder if the torque converter could be the cause. I wish I could test drive another TL that recently had the converter replaced for comparison. Maybe my local dealer has one on the lot.

 

vtec is 5000RPM and beyond.
if you're only hitting 5k, you are not in the proper power band to continue into vtec...

Dont know if you were using real life examples or just made up numbers....
also, check your oil. vtec operates via oil. if low oil, car wont allow you to enter 6K and beyond

 

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The ECU engages VTEC based on a number of factors (oil pressure, engine temperature, vehicle speed, engine speed, throttle position) and is supposed to have hysteresis, which mine does not seem to have.

Numbers are real +/- 500 RPM.

Oil level is fine, but spool valve gasket and/or o-ring(s) have a small leak.

FYI, I recently switched from conventional "bulk oil" to Mobil 1 synthetic, and have noticed a significant drop in gas mileage. The oil is also a medium brown. I haven't had the vehicle long enough to know what is "normal", but I think I'm going to switch back to conventional next time. Also going to fix the spool valve leak.

 

that's what it sounds like with the example you gave. For some reason, it's dropping out of vtec, unless you can hold that gear well into 6K RPM.
we make the most power or peak power at like 6900 RPM, very close to 7k.

 

I have a 6MT 2006 TL, and I want to say when I hit redline, it drops back down to 5k, still in vtec into the next gear.
but im not sure, as my memory is horrible and since we have two different transmissions, one might be geared better than the other

 

cant tell the condition of the oil based on color, BECAUSE some oil is intended to change color.

 

I think I'll try using sport mode and keep the RPMs above 5k. If that resolves the issue, I'll know the problem is with the VTEC disengaging. Still hoping this isn't normal. The ECU should know that if the engine is under a heavy load and the accelerator pedal is floored, that it should remain in VTEC. I could get creative and temporarily connect an LED to the VTEC solenoid and monitor when it turns on and off

 

I've noticed this same issue on my 2012 FWD as well. It's only ever happened to me once, and I haven't tried to reproduce it yet.

For reference, I use Pennzoil Platinum 0W20 synthetic oil and a Purolator PureOne oil filter. I'm currently at 70% oil life, but I can't remember if I was on the new oil or old oil when I had that upshift lag. Like you described mossman, it feels like the brakes are being pressed briefly in between gear changes.

I'm going to have the transmission software updated hopefully next week, so we'll see if that has anything to do with this.

 

ECU closes the TB during shifts and fuel injectors for better MPG, as well the ECU has programming designed to limit Torque to prevent transmission damage. Depending on your tires, you could be having wheelspin during shifts and VSA is applying the brakes.

 

I wasn't actually flooring the accelerator pedal in the past. I was probably at about 75% throttle. Yesterday I put the pedal to the floor, the RPMs got to about 6,500 and never dropped below the VTEC threshold (4,700 RPM). The "shift lag" was not evident. So apparently the VTEC is disengaging unless I'm at WOT. This is unfortunate because I don't want to have to floor the accelerator to keep VTEC engaged. It is my understanding that VTEC uses several factors when determining when to engage/disengage, not just RPM, so IMO, it should be staying engaged when less than WOT.

 

i have a 6MT, so I can engage vtec whenever I want.

 

I couldn't find a 6MT for the life of me when I was looking. Probably because of the airbag recall.

 

sucks that you have to be in certain parameters to keep vtec engaged

 

#autotragicproblems..

 

I'll just install a momentary pushbutton switch on my gear selector to override the ECU and keep VTEC engaged as long as I want

 

Or Buy a manual