Losing bottom end power and engine temp gauge crazies

Harbor Freight is a nice store. Cheap taiwanese tools and an extremely low price. Great for the home mechanic but really bad if your using them professionally. Most of my tools come from HF with the exception of some air tools. Just like 4thgenceli...jack stands, sockets, wrenches, you name it they got it.

 

T-vis shouldn't even be open below 3000 rpm. I do believe T-vis is designed to boost bottom end power,
perhaps your T-vis is intermitently stuck open. I don't know how much power you loose with a stuck open T-vis.

 

I have a feeling your ecu is in limp mode, causing the no load/power bottom end.


Remove the ecu power fuse or disconnect the battery and see how it goes. Trust me, i have experienced this with my 3sgte starlet.

 

Is that in neutral? or only while driving
It could just be the throwout bearing has some play on it- put pressure on the clutch fork with your fingers, if it goes away the bearing is loose. Irritating but not damaged

Heaps, the bottom end dies but it runs normal higher up.
You need to see if the TVIS is free - if not it may need cleaning, normally they stick partially open and won't close properly which means bad torque and the top end feels limp too

Does it smoke under acceleration? smoke when starting in the morning?
If so, there's oil being blown into the intake and causes the symptoms you describe, plus it will clog your cat and O2 which screws with the ECU

 

Great news on the tranny, It's amazing how a full box of decent lube improves things :ewink

For those that may be interested........ Brisbane to Rockhampton is a nice full on coastal test drive for the car/econometer as Rocky is approx 600km one way or 7½ hours of driving time.

I look forward to your 'report' on both Aaron :fingersx ............... Rocky sux in my opinion but still, come back safely.

I nearly forgot, are you going to try and catch up with Kevin (Stig) in Noosa or wherever ?


TVIS info and I quote :-

Toyota Variable Induction System, or T-VIS, is a variable intake system designed by Toyota to improve the low-end performance of multi-valve engines.

T-VIS is intended to improve the low-end torque of high-performance, four-stroke internal combustion engines - by changing the geometry of the intake manifold according to the engine rotation speed. The system uses two separate intake runners per cylinder, one being equipped with a butterfly valve that can either open or close the runner. All valves are attached to a common shaft which is rotated by a vacuum actuator outside the manifold. T-VIS does not actually keep one of the intake valves from opening or seal off the port for one valve.

The engine control unit (ECU) allows vacuum into the actuator by powering a solenoid valve when the engine rotation speed is low. At higher engine speeds (e.g. 4,200 rpm), vacuum is cut off and a spring inside the actuator causes the butterfly valve to fully open.

The idea behind the system is that in the lower engine speed band, the speed of the intake air will be increased because the intake runner cross section per cylinder is smaller. However, when engine speed increases, the second runner is opened, decreasing airflow speed, but increasing the airflow volume, better matching the engine's airflow needs at higher revolutions.

With modified engines it may be desirable to have the T-VIS open earlier than stock, because modifications that improve an engine's power output may do so by increasing airflow per engine revolution, resulting in a high airflow at a lower rpm.

In addition to providing more air at higher engine speeds, the system also creates a swirl in the combustion chamber at lower rpms. The swirl makes for more efficient combustion, and is due to the asymmetric nature of the airflow with one intake runner closed.



****** This is also very interesting, the dude that posted it should have used an easier reading font, if reading it starts to give you the shits then just copy and paste it into a RTF document and change the type of font........... http://websworld.org/marcel/tech/tvis/tvis.html