You nailed it on the voltage regulator it is sending too much voltage to the engine. It is making it overwork. I noticed thats why mine didnt work as well it was rebuilt with a non denso voltage regulator. Everything was fking up even my transmission pump. I was driving on it for such a long time i started hearing bad noises fromm my engine area and knew i need to get my idle right because id be braking and the car would keep trying to go forward.
The idle should be at 750 rpms, and car shouldnt push forward when braking as there is a module that detects when braking and lets off throttle in a ratio

 

@JaredAU After driving for say 10 to 15min, what is the battery voltage at? Hopefully something lower than 14.2 volts.

PS - maybe grab a 12V USB adapter with voltage readout and you can sorta keep an eye on it.

I mention this as 14.2 sustained will take the life of a battery.

 

Very glad you fixed your problem too mate!
I'd be very much interested in the idle video as my new alternator causes my RPM's to fluctuate while the car has no load on the battery. As soon as I turn any exterior headlight on (even the safety lights) the car idles fine and doesn't fluctuate. Here's a video I had with the problem.

I'll measure this today and report back!
May I ask what device you're talking about, I couldn't find anything online that matched the same description.
Thanks for the reply as always @2013FSport

 

Like so 12v cigarette lighter to USB w digital volt meter.

FWIW I have 3 fluke meters that all have Min/Max functions that help us understand what our electrical systems are doing / not doing.

For example, when starting a car and the meter momentarily captures a voltage of 9.6volts and us as humans only see a digital value of 10.5, we assume it should be okay. The fact is, it is not. The electronics will not operate at this voltage.

Read here on min max function. It's a life saver with over / under voltage data capture. https://www.fluke.com/en-us/product/...meters/87v-max

Hopefully there are cheaper solutions but that's one of the tools I have.

 

Thanks for this! And its a great idea to keep an eye on the voltage through one of these devices!
It's really expensive when factoring in shipping costs and conversion to Australian dollars, would this be a suitable substitute?
https://www.ebay.com.au/itm/22512538...Bk9SR9jzqLOSYQ

Also, do you have any idea of the RPM fluctuation problem I'm having with the RPM spike?
The only thing that stops the alternator from fluctuating the RPM's like that in drive or reverse is if I turn any exterior front light on.
Also, the fluctuation only happens after I'll be driving and i come to a stop and the car RPM's dip as I brake.

Thanks again for your reply! and I'll keep a look out for a better min/max multimeter too

 

Yes, that would work but keep looking. You either want a rectangle shape that fits an unused dash plug to hard wire in or for example the round one I offered fits in forward most cigarette lighter 12v socket.

https://www.ebay.com.au/itm/194020839094 <example only. No clue if it fits Toyota dash.

https://www.ebay.com.au/itm/403654170038
The price seems scary cheap. I may not trust it but take a look.

 

Appreciate the help mate. Thanks again for the replies!

 

Clean your battery cables and terminals. It looks like you need to relearn the idle again if this doesnt work. pull fuel injector fuses. Its like on the opposite engine fuse box of the steering wheel/battery. You pull like three fuses or maybe 4. They are all fuel injector fuses, and control. Then after 30minutes, to an hour, turn car back on. let it idle till the car is warm BUT MAKE SURE you turn off ac radio head lights before you pull fuses. Push button no foot on brake, press acceleration pedal all the way down and let off. Turn off car. Repeat 3 times. Turn on car. Idle should be high, dont press the brakes or anything after it turns over, just let it idle for like 10minutes it will catch and level out and go down real slow. Jared if this doesnt work, You might have damaged your entire intake manifold or injectors from shooting degreaser into the intake.

 

You also need to clean the shizz out of yoir battery cables, but becareful i cleaned off a silver coating and now copper shines thru. I dont know the effects and i assumed it was grit and dirt. it looks like it was a protective coat actually in retrospect. I cleaned the cables because I had a check engine light come on after the alternator got fixed and it was a high or low voltage code. I just had to clean the terminals immensely. I noticed the car drives incredibly weak and slow with the bad alternator or battery issues. With a good alternator the throttle has pressue and a smoother response with alot more power and extremely low fuel consumption i am averaging 25.5mph while flooring it around on the highway. I think that as a last resort you have a low transmission fluid level, or the incorrect fluid type. It could be a torque converter issue with the idle, but it looks like your idle needs to be relearned. Also make sure your negative ground on the alternator is flush and lined up in the two notches. And the alternator wire isnt burned where its near the exhaust, and the wire is pushed all the way on.

 

that tool is pretty darn good if it works..! Like damn

 

Sometimes my vehicle drives weird though still after this alternator and i dont understand why. I might have a transmission issue because it just wont go into gear 6 at times, unless i let off my gas pedal on the highway. It forsure should have shifted and it will delay the shift till i let off the pedal. Does anyone know or have any ideas. Im pretty confident my fluid is the right level i changed it out and evetything but i used ATF WS not toyota and then also like the car will kinda accelerate on rpms when braking and downshift but not push forward anymore its like i have to have the transmission relearn the shifts i hear the dealership has to reprogram the transmission after a fluid swap i dont really know because i dont use the dealer i use online and driveway

 

If you read enough threads, 5th to 6th when on a slight incline will mess with how these cars are programmed. You are not the first and I can tell you that mine does the same thing. At first I thought it worse when cold (20% more noticeable) but it can easily do the same thing when warm. And one has to add a good bit of throttle once it's made up its mind on an incline.

Can you connect the same dots that a slight incline is the cause?

 

@2013FSport It drives amazing on hills now i can feel the increase of throttle and power its really an amazing vehicle and different type of car much better than anything on the road i can feel it. This issue with accelerating and decelerating i heard can be ecu but i tried replacing ecu with a reprogrammed one. it didnt work. it might be through the codes i threw earlier along with the p505 like the codes above i posted around 4-5 codes. These are for yaw rate sensor and more angular sensors, however my codes went away.. it appears that the hill climb sensor is working great maybe the other sensor, the one for accelerating and decelerating is having issue. I noticed there is a normally a pool of water in my trunk in the rear left under the matts and it always accumulates even after i vacuum it up... i think one of the sensors are located there...if i remember right.......i don't know if there is a diagram for that sensor ill have to check around. The alternator issue definitely fixed p505, and the car is running great, but as you know i am having issues with my rpm when braking. I redid my front brakes the entire caliper bracket rotor and pads, i cant tell if its actually still accelerating forward and my brakes just stop better, because theyre powerstop pads and rotor and oem dealer shim which improved alot of issues with brakes and but i did not do the rear. i have a powerstop kit for rear with rotor. i noticed my front is overworking and kinda shaking now unfortunately.. but i alsoredid my control arm bushing with oem, which are gas filled. and the wheel bearing with koyo hub, and oem ball joint and tie rod but i noticed the upper controtl arm ball joint was floppy lose on both sides and i need to do those, and i also have delphi shocks which feel strong but my god tier alignment shop said i need a new shock on the front left where it shakes..i tightened everything already. but i didnnt have the 17mm impact for the other control arm bushing bolt..its been a pain. i think if i do the rear brakes it might decelerate better...?

 

i actually dont even move my foot and it speeds up on hills bro im telling you its an amazing car

 

it just started that hill performance increase after the alternator got rebuilt with denso kit