HELP. 1/8th of throttle is dead

Hey everyone,

I just recently cleaned my throttle body and MAF sensor on my 04 3.4 Tacoma. This model has no IACV and has the “hybrid” throttle body.

After reinstalling everything and taking it out on the road I’m getting a dead throttle until I pushed the gas pedal in about an 1/8th of the way.

My throttle body cable is tight and it reacts the same whether or not the car is on or off.

When I manually pull the throttle body cable I can feel the throttle body open after about an 1/8th of movement.

Idle is fine, sitting at about 700rpm.

Other than the pedal problem, everything seems to drive fine.

I’ve read on the APPS and the TPS. I’m not sure if mine is going out or not. But, it seems like I don’t have any of the symptoms either?
Thanks

 

Welcome aboard new member

 

almost sounds as if there is a slight delay in relaying that the TB is rotated. everything is computer controlled and I haven't figured out if the software can adjust the sensor or not since I don't own it :\

 

Yeah I’m not sure what’s wrong with it. I hope someone that has experience with this comes and chimes in. It feels as if my throttle body cable is loose when really it’s not.

 

You have checked in the cab that nothing is broken ?

that 1/8" could be flex in the floor

Although since my floor broke and was fixed I have close to a inch of movement I no longer even take notice.

 

There may be a reset/zero procedure needed. With toyotas in my experience it is usually something like this:
With key off, push gas pedal to floor and hold it for 10-15 seconds then let off, turn key on repeat, turn key off, then start truck or something like that. I found out "SURPRISE" that I had to do that when I unplugged my throttle pedal one time, except my throttle was totally dead. No anything until I figured that out, luckily I had heard tales of similar issues before and played with it until it worked. Good luck figuring it out OP

EDIT: you might also try unplugging battery for 5 mins as well

 

Thank you guys. I’ve tried the push gas pedal in and turning it on and off. Still nothing. I’m not sure if this is the same for you guys or not but I’ve read that the throttle body is supposed to make a whining noise and click when opening and closing. When I open up the throttle body it doesn’t whine or click until I hit the 1/8in spot of gas pedal pressed. Is it supposed to click right as the gas pedal is pushed in? Or is this extra gap there for “safety” purposes. Or is the ECM supposed to read that I’ve already pushed in the pedal and fill that gap?

 

As I understand it, no there shouldn't be much play in the throttle cable, but if the cable is tight but the TB is unresponsive for a time, I would look to see if there are any adjustments on the TB itself rather than the throttle cable adjustments.

 

How do I adjust the throttle body itself?

 

Should be a few adjustment screws on the side where the cable mounts. One of them will be for idle setting so I wouldn't touch that, but there may be one to adjust the plate where the cable meets the throttle body, I am not 100% sure only going off of experiences with other TBs in the past, but it's somewhere to start

 

Hmm, I’ll look into that. Just odd because my throttle body cable is still tight. Pressing the pedal in pulls the cable but it has to be pushed in about an 1/8th before it even opens the throttle body.

One thing I can do... tighten the cable until it hits the sweet spot of opening the throttle body. But... I’m scared that if one day my ECM reads that my pedal is pressed in and I’m backing up or something it’s gonna launch my car.

 

Yeah I wouldn't just tighten the cable without knowing it's loose, it's supposed to have a small amount (1-3mm) of play. Have a good look at the rest of the TB, maybe the clock spring is bad?

 

yeah that’s how the throttle body cable is atm. It’s nice. If you take off the assembly where the throttle body cable is attached to the throttle body is there supposed to be about a 30 degrees rotation on the little nub that makes the throttle body open and close?

 

I attached an image.

So, I took this apart to investigate some more. It’s attached to the throttle body where the throttle body cable attached to.

When I disassembled it, I turned the notch that opens and close the throttle body and it has about a useless 30 degrees rotation where it doesn’t close or open the throttle body. Could this be my culprit? Or is the ECM, APPS, and TPS supposed to all communicate to know that I’m pushing the pedal down?

Just ordered a 4 prong TPS for my Throttle body. I guess I’ll see if that’s the culprit even though I don’t have any of the symptoms. It seems as if a lot of people have problems with them so it doesn’t hurt to try I guess?

 

that's the way it's supposed to work. once you press the pedal the APPS reads how much, then tells the ECM to turn the TB motor, which the TPS reports back that is has moved.

the delay in movement is "limp mode" if the ecm can't communicate with the APPS, TPS, or TB so you can slowly creep down the road if needed with about half throttle.
this is one of Toyota's first drive-by-wire systems

 

Okay, yeah I read that in your other thread from a few years back. Thanks for all your help. Will update once I get the TPS in a few days here and see if that makes any difference. If it doesn’t then idk.

What would make the sensors not be able to communicate with each other and put the system in limp mode? I guess it could be a number of things... Why couldn’t I have had a pre 03 TB lol.....