90 tr4 v6 auto lack of power no downshift

[feelblades1]

Hi everyone! new to the site, I bought a 90 tr4 v6 4x4 auto today for$800 and I have a few questions, first off the truck has 217k and is a lil rough. the engine seems to run smooth and the oil and coolant look pretty good (doesn't look like seller just changed them to hide problems). my concern is that the engine has a high idle (1100-1200rpm) and lacks power severly. I test drove the truck and with pedal to the floor the truck would not down shift and took forever to get up to 45mph, there was no bucking or hesitation, just a real lack of power. has anyone had a concern like this? I am somewhat mechanically minded (was a gm technician back in the late 90's) so any input would be great!

 

[ToyoTech]

check timing. 10 degrees is stock
check the o ring for the idle screw.
check for turn intake boot. remove for better inspection.
does it go into overdrive once warmed up? or does it take forever to get into overdrive? if so. mine did that and ended up being a stuck t stat

check the adjustment of the kick down cable, attached at throttle body and ends inside the tranny. its common for the cable to stick or break. may need cable and will need to drop tranny pan to change it.

after i made sure everything was good. tune up done, true warm up temp confirmed. i still had high idle and turning in the idle screw all the way in works but it should never be turned all the way in as its just covering the issue. mine ended up being a weak/worn out idle air control valve. for the 3.0 its part of the throttle body and you have to change the entire throttle body to fix it. i didnt do that. i ended up taking the throttle body off the engine and took the cover off for the iacv. i just turn the valve inside it till it bottomed out. this basically disables the iacv. this means, at start up, it will never have cold idle. since i garage mine i wasnt to worried, i can always hold the throttle open manually if i needed to. so far it hasnt been any harder to start. i also disconnected the cold start injector connector since i dont need that going when it is already gonna start up at correct idle ~800.

 

[feelblades1]

thanks toyotech! I will definately start looking where you told me this weekend and I will report on my findings. I am accustomed to american made vehicles and this is actually the first foreign made vehicle I have ever owned, I am sure it will be a lot of schooling for me, I appreciate any and all advice, thanks again!

 

[feelblades1]

I took your advice toyotech, and i found that the timing was off, (previous owner had replaced the alternator) and i also found that someone had broken the release tab off the connect that plugs into the tps and had taped it up, but it was not making connection! fixed all that and it runs great! I also had to do a lil adjusting to the kickdown cable, she shifts good but very had into overdrive, (i am hoping that it is just the trans mounts worn, no slippage, just hard)

 

[KidVermicious]

I took your advice toyotech, and i found that the timing was off, (previous owner had replaced the alternator) and i also found that someone had broken the release tab off the connect that plugs into the tps and had taped it up, but it was not making connection! fixed all that and it runs great! I also had to do a lil adjusting to the kickdown cable, she shifts good but very had into overdrive, (i am hoping that it is just the trans mounts worn, no slippage, just hard)

I came in to recommend you check the TPS and connection. Glad you got it squared away!

 

[feelblades1]

OOPS! sorry kidvermicious! your post didn't show up on my comp! but thanks! this site is great!