2007 Tacoma throttle response lag

New to the forum and recently bought a 2007 TRD in great shape. 6spd manual. When I shift.....the engine seems to continue to rev rather than back down like I have been used to in previous cars and trucks. It is almost like the throttle return spring is weak or something. A mechanic told me it is something common to Tacomas? Any insights?

 

If u mean when you step on the clutch and the rpm's bump up a few hundred or like 200rpm, than that is normal. I exp it all the time, if that's what you mean

 

Common on the manual tacos.

 

This situation doesn't seem to have anything to do with the clutch Dday. If i punch the gas....and release.....the engine seems to keep reving....and slowly back down even without the clutch engaged.

 

My 07 has lots of quirks I noticed. I knw idle is 7-800 rpm or whatever, but when moving, and hitting clutch, my rpm drop to only 11 or 1200. Maybe a sho phone vid to demonstrate.

 

I think i have learned since posting.....that the 07 and above are not connected to the Fuel system with a cable.....but instead with "throttle by wire" which I take to mean that the foot feed is connected to a computer which governs engine speed. What I am feeling could be explained by that.....the computer just has some lag for some reason....in calling for the rpms to decline?

Someone mentioned you need to need to learn to shift like a dump truck....ie...some hesitation after releasing the throttle.

I am able to handle the situation now......but it seems unnatural. Thanks for all your insights.

 

It's an emissions control thing. Holding the RPM momentarily produces less emissions than having the RPM drop off straight away.

 

^ This.

The reason is that if the engine is at higher RPM's and the butterfly valve suddenly snaps closed, any fuel still being injected (before the computer can catch up to the changing conditions) will not have sufficient oxygen to cleanly combust. This theoretically cleans emissions and extends the life of your catalytic converters.

 

Clean your throttle body, clean your maf sensor, run a 12gauge or larger ground wire from one of the throttle body bolts to a ground point on the frame.

Odds are that should fix 75% of the issue

 

What is the ground wire supposed to solve? First time I've heard that.

 

???? Why a ground wire, what does it do?

 

^ I actually heard of a member here doing it and I was also very curious. Did some research on it and it is actually factual although no one necessarily knows why. The thought behind it is that since the throttle is a drive by wire system directly grounding it lets your throttle and the tb sensor communicate with less noise since its not going through the more "noiser" factory grounds. I did this on my 650rwhp '09 cts-v and it actually worked. Got a bunch of other V owners doing it on their cars and they ALL have said they noticed a much better improvement in idle, throttle response, predictability of throttle. Like I said 12 gauge / 10 gauge with a reg loop end and ground one of the 4 bolts to a ground point in the bay. It works

 

yup x100000000000091354

 

Curious. Thanks for the tip. Can't hurt to try. It it takes such large gauge wire, I'm wondering if line resistance isn't the problem instead of noise? These electronics work on small voltages so even a small grounding problem could have effect. The TB is a bit isolated I believe. I need to go have a look.

 

That sounds like a dealer's BS line. In this day and age of lightning fast computer controlled port fuel injection, I don't understand how this makes any sense. I also don't understand why other vehicles (that have the same kind of fuel injection and fly by wire throttle) don't have this throttle lag. I think more likely it's a design flaw.

 

yea there was a big bullshit thread talking about this a while back. the OP was swearing by it and I was telling him it wouldnt work... I never saw any evidence of it working.

change your blinker fluid while your at it

 

Common on the manual tacos

Ditto... my truck does the same thing. I noticed when the engine is cold it does NOT do it at all. So maybe it's an emissions thing.

I don't buy that it's to reduce emissions. It's not normal.

Any other fixes known?

 

As someone already mentioned here, for the manual trans when the clutch is depressed the rpm bumps up instead of down due to the Drive By Wire system. Something to do with emissions, etc.

I did however want to comment on the grounding the throttle body. I don't know if doing that yields better throttle response. shifts, etc but it is possible. I know there are factory grounds already and it's not necessary to add additional grounds to the vehicle but having additional grounds would not hurt either since our trucks function within an electrical system from top to bottom. Think of it as a 5 lane highway versus a one lane, there's just more pathways for electricity to pass more efficiently. Same concept when wiring up a stereo amplifier with a thicker gauge wire versus just using thin regular wires. Sure it will function but I sure doubt they will function the same. Why didn't Toyota just use better grounds? Due to cost perhaps. Why use 89 octane versus 93? They both work yet Toyota has different HP/TQ rating for both octanes.

 

^ Toyota lists the higher values at higher octane. allows ignition timing to advance without "pinging"

my truck does it too, made for a lazy ass person i guess. has anybody tried one of those in-line throttle speeder-upper things. called Sprint-Booster and plugs in-line between foot tps and control motor/tps?