Throttle Body Valve only opening maybe 45 degrees max.

Hey guys,

So I did my spark plugs yesterday and while I was at it I wanted to do a quick clean on the TB valve. I noticed that when I manually turned the valve as well as when I had someone press my gas peddle all the way in, the spool turns with the gas peddle, but the peddle is at least 50% in before the TB valve opens, and when all the way to the ground it made opens 45 degrees max. Is this a problem and what is the fix? I adjusted my throttle cable tighter but still doesn't open the valve more. I have a problem in first gear where the truck is very slow to engage and get moving. I wonder if this is why?

What are your thoughts?

It is a 2004 3.4l V6 4X4 Tacoma- manual trans.

 

ECU tells it how far to open. Throttle by wire.
Remember when this came out how many lawsuits there were from people claiming their throttle stuck wide open?
Now the vehicles are older and would seem to be more likely to fail, yet occurrences have dropped way off, hmmm.

 

"drive-by-wire" is a misconception. it's more or less that but by no means perfectly named. the reason it only opens that far is "limp mode" for when your ECM cannot control the TB butterfly valve. it will allow you to at least drive the truck to a safe destination. with the '03-04 ECTS (Electronic Controlled Throttle System) when you push the pedal there are 2 sensors that communicate telling the ECM to open the butterfly via the motor mounted under the TB. even if you turn the round cylinder where the throttle cable connects all the way it will not open more than that.

do you hear any rubbing when you turn it? they have been know to move side to side due to wear on the actual butterfly flap and come in contact with the sides of the TB.


the throttle epidemic was 05+ models with the 4.0, could have even been 08 due to more electronics.

 

Time to remove the throttle body and go for a clean up. You may have a shit ton of gummed up dirt and grease in there.

It is not a hard job but it will take a few hours of your day. Take pics of it before disassembly...cause you might have a hard time with those vacuum lines upon reassembly

 

https://www.tacomaworld.com/threads/3-4l-w-etcs-tb-cleaning.324673/

 

I am guessing you don`t have any codes

That would tell you your stuck in limp mode ??

 

gah, you're right. my sense of time is getting worse. It was the '08-'10 years that had everybody freaked out.
Guess they got rid of the cable altogether that year.
I like the mech. feeling better but I've had stuck throttles quite a few times....all with cables.

 

Hey guys. So I posted my throttle body issue over at T4R.Org but haven't gotten much response. It's on my 1997 4Runner 3.4 five speed manual. I just did a valve cover job and spark plugs and wires and all that jazz. I cleaned the throttle body and IAC very carefully but due to the throttle body having 370,000 miles on it I developed the Apparently pretty common high idle. It overall ran fine but unhooking the battery for several hours did not do the trick to get it to idle normally. Up to temp was idling around 1200 RPM. I came across the washer mod where you separate the linkage from the throttle body and slip a thin washer on the rod and then reinstall the linkage and that is supposed to get it to idle fairly normally. Before I started I did pull forward on the linkage and the idle dropped down to around 700 so this would have cured my issue. However when I finished up and started up the truck the throttle is stuck wide open now. I am pretty sure I have everything installed correctly and I think there's pretty much only one way that it can go back on. Cruise control cable and throttle cable are both where they belong. Also the accelerator does not want to push down at all. Not super knowledgeable with this so I'm a little stumped. Any advice would be much appreciated. Thank you.

 

The accelerator not pushing down will lead you to the binding.
Seems like it's routed backwards or something to that effect.

 

Yeah I'm pretty sure it's routed correctly. Cruise cable is routed the same way and throttle cable routed the same way. I dont know if you could even get the linkage back on all the way pressed against the washer incorrectly and still route those cables. To look at it, it looks completely normal. But by hand I can barely move the throttle linkage and like I said the accelerator will barely push down at all . It seems like the throttle cable is just stuck or something. When I get back home in a couple days I'll remove the upper intake and see what position the butterfly is in. I'm coming along but still pretty new with this mechanicen stuff so any other thoughts. Thanks for the reply man, especially since it's been 5 years since your last post

 

Last post in this thread I mean

 

You might just need to get the throttle body re-bored. They wear out over time/mileage. The butterfly valve wears away at the metal and after you clean all the gunk away, there's space for extra air to get in which causes the high idle.

MaxBore is a company that will re-bore it for you make it good as new

 

Yeah I called and talked to him. The truck ran good after I cleaned the throttle body. It wasn't until I removed the linkage to attempt the washer mod that I ran into this problem. George at maxbore told me no guarantee on the success of him reboring mine since I removed the linkage, which he never does apparently. With 370,000 on it I may just buy a new one. New sensors, IAC, etc..hopefully that'll do the trick.

 

What happens when you disconnect the linkage?

Does the pedal move freely and all binding is in linkage?

Disconnect linkage from throttle body and binding is in throttle plate?

Binding is in motor under throttle body (tiny electric motor, not your engine motor)

Just narrow it down before throwing an expensive part. (Not that we haven't all made that mistake )

 

Yeah man I'm gonna get out there tonight after the fam goes to bed and mess around with it n get some clarity on those questions. I'll pull the linkage off n see what the gas pedal feels like first. Gonna remove the intake and see what position the butterfly is in, etc. And I'll wait until after my friend comes over and takes a look at it before throwing down on a new one. Good advice . I'll definitely let ya know what we find out/or not, and again appreciate your feedback Sir