knock sensors replaced.. now hard shifting

hey all, new here posting but been reading the valuable information for years-

i just replaced my knock sensors and harness 3 times(!), with the last time using actually Toyota OEM sensors and harness from the dealership. seems to work finally. however, it is shifting QUITE hard, particularly overdrive (4th gear). i drive it from truckee to verdi and back again, which is 20 miles each way and steep. i kept in OD OFF as i always do when going uphills with the big six-pac camper i have on the back (~1500lbs), so maybe it hasn't had time to relearn that gear shift as well.. but while it idles fine, it does seem to have lost power in acceleration, and the 4th gear shift is fairly hard. will this round itself out over the next 100 miles? gah im so scared i messed up something worse now.

thank you all in advance!

 

ALSO!
225k miles, trans rebuilt where needed at 180k, valve covers at 160k..
i just replaced the spark plugs with iridium, knock sensors and harness, new gaskets except for the top intake plenum as the metal one was fine, new pcv valve, new air filter, been regular with oil changes, trans fluid is fairly fresh and level. new battery and alternator at 185k as well. it's in good shape, but this knock sensor replacement was a pain in my arse. but i think it did everything correctly this time, even replaced a lot of the bolts and nuts. anyway there is more info.

 

Double check all the grounds that bolt to the engine. Are any loose/not bolted in?

 

nope, they all look good. there are 4 different cables that connect to one ground source, and they seem fine. also, this problem has only started since i did the 1st repair, but haven't driven much until now- hopefully it learns and that's what happening. just seems bizarre, never felt any thing shift like that. i did add a negative from battery to chassis just to see.

 

On the throttle body there are either 2 or 3 cables depending on if you have cruise control. Locate the cable that goes from the throttle body and goes alongside the upper intake manifold down to the transmission. Where the cable connects to the throttle body bracket you will see a black rubber end, pop that off and look at the crimp sleve, it sould be flush with the outer portion of the threaded cable end. Loosen the 14mm nut(s) and adjust the cable length. This adjust the pressure inside the transmission that controls the shifts. I can not emphasize enough how critical this adjustment is, if you think you are going to adjust your shifts so that they are nice and soft there wont be enough pressure inside the trans to hold the clutch packs/bands etc and you WILL smoke your transmission.

 

i fiddled with the cables and got it as true as i could, using both what you said and pictures i took before the operation (i counted threads to judge tightness). still same old. it threw the code p0120 for TPS but it went away not long after, i think when troubleshooting i had it unplugged when it was on.

i've checked all the hoses and vacuum lines and everything looks good. the other big thing now and what started when i first turned the car over after this last knock sensor replacement (which seems to have fixed THAT), is this whirring almost grinding noise both on startup and then when i accelerate. almost sounds like a pulley or belt but lower pitched, and there's no way that that is an issue that co-occurred coincidentally with this repair. all lines lead to an improper seal somewhere but i can't find it.

 

apparently brake cleaner isn't supposed to go into the throttle body.. i sprayed a little in the other day to clean the butter fly valve not thinking anything of it. now it seems the consensus is that could have ruined my iac or tps, causing the whirring sound and rough shifting. i really didn't spray that much but i don't understand how harsh that stuff is or what's going on in the iac or tps, throttle body area. does this sound like it could cause this big of an issue?

 

Dumb question. How many miles on the serpentine bent?

 

not entirely sure, i bought truck at 175k and i know the previous owner had done some decent work on it. at the very least 50k but likely more

 

Maybe the belt is old and slipping.

 

would that cause the transmission to shift that hard though? and the chances that it started slipping only after this last repair seems odd. but i hear you. the sound does seem to be coming from closer to the tps/iac than the belts but ..

 

Have the driveshaft ujoints and center bearing ever been replaced?

 

yep, all in the last year or two

 

i've tried everything- took off and cleaned throttle body, replaced tps and iac, messed with the kickdown and throttle cable many many times. replaced the grommet for the pcv valve as well. still shifts hard as hell. manual shifting is ok. the whining noise i believ is the pump on the transmission working at 100% line pressure, but that seems to be getting quieter(maybe..). pulled the ecu fuse and reset it. my scangauge reads my tps either at 5 or 7 (percent i imagine) at idle and i have zero issues with idling. the ONLY issue seems to be the trans shifting very hard.

 

Maybe clean and lube the solenoids in the trans. I don’t know, shit. Good luck.

 

You gotta post pics of where you have the transmission pressure cable adjusted to. The way people sometimes describe the right position is wrong.

When you put the large cable bracket back on the driver side of the intake manifold, did you put it in the right position? For some reason there's two bolt holes, and one makes it too tight.

 

well i never took the bracket off as it doesn't need to be removed- but yes i'm 100% sure i put the cables in the right place- and i tested them in different lengths both tight and loose and in the middle. nothing seems to have changed, even with a fair bit of slack in the kickdown cable.

 

As you’re coming to a stop with your foot on the brake does the trans feel like it goes into neutral or does it feel like it’s still in gear when stopped?