TPS readings range from 14.1 to 79.6

2004 3.4 V6 4x4 TRD off road with 180,000 miles bought used at 165,000

After a long trip it started to have subtle hesitation at light throttle. At highway speeds (60 to 70 mph) with or without cruise it would loss power for a few seconds and then roar back to life and have power. Same thing happened at light throttle when leaving stop lights in town. It would not die, just have no power for a few seconds. This was happening about every 5 to 30 miles. It seems to be worse on long (3+ hour) trips. Very intermittent. I took it to a toyota dealer and they replaced the MAF sensor because the reading were "too low". The problem was gone for about 2 weeks and then started to happen again. I cleaned the throttle body (it was very gunky and dirty) and replaced the fuel filter and replaced the air filter. The problem was gone for about 2 weeks. Fuel mileage might have gone up about 2 MPG, but my driving is too varied to know for sure.

As part of this debacle I have also started to swap the CAT and it looked very clean and I don't think it was the issue. The original CAT is still in it.

I picked up a Bosch scan tool from O'Reillys a while ago. There are no codes and no check engine light.

The scan tool shows the TPS ranges from 14.1 % to 79.6 %. Never more and never less from idle to full throttle. Should it read closer to 0% to 100%?

When cleaning the TB the plate does not close all the way. When pushed shut it will close. Yesterday I looked the TB again and there was a small amount of gunk (black sludge).

Any ideas on what is causing this hesitation? Anything to check?

 

Logically, it would read 0 to 100. My scan tool shows the same range as yours on my 3rz though.

 

I had the scan tool hooked up today and recording data when the issue happened between the following frames. It looks like the ignition advance went back 10* without a real reason. Any ideas? So much data and not a good enough idea what some of it means and how it relates to performance.

FRAME: 10 TM: 31.9

ABSLT TPS(%) 18.0
CALC LOAD(%) 25.9
COOLANT(°F) 198
ENG SPEED(RPM) 1784
EQ RATIO11 0.961
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
IAT(°F) 93
IGN ADV(°) 27.5
LT FTRM1(%) 0.0
MAF(LB/M) 2.30
MIL STATUS Off
O2S12(V) 0.410
O2S11(V) 3.352
OBD2 STAT CA
ST FTRM1(%) 3.1
VEH SPEED(MPH) 53

------------------------------

FRAME: 11 TM: 35.1

ABSLT TPS(%) 24.3
CALC LOAD(%) 53.7
COOLANT(°F) 198
ENG SPEED(RPM) 1774
EQ RATIO11 0.996
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
IAT(°F) 93
IGN ADV(°) 14.0
LT FTRM1(%) 0.0
MAF(LB/M) 5.20
MIL STATUS Off
O2S12(V) 0.445
O2S11(V) 3.265
OBD2 STAT CA
ST FTRM1(%) -0.8
VEH SPEED(MPH) 56

------------------------------

FRAME: 12 TM: 38.3

ABSLT TPS(%) 25.1
CALC LOAD(%) 51.8
COOLANT(°F) 196
ENG SPEED(RPM) 1839
EQ RATIO11 0.999
FUEL SYS 1 CLSD
FUEL SYS 2 N/A
IAT(°F) 91
IGN ADV(°) 20.5
LT FTRM1(%) 0.8
MAF(LB/M) 2.57
MIL STATUS Off
O2S12(V) 0.425
O2S11(V) 3.191
OBD2 STAT CA
ST FTRM1(%) -14.1
VEH SPEED(MPH) 55

------------------------------

 

is this 2004 drive by wire or is there an actual TPS sensor bolted on and connected
to the back side throttle plate shaft ? cuz if you can find it and replace it with--->OEM only<---
problems could go away. worn out TPS causes all sorts of buggery
and an OEM one is just under 50 bucks. It cured my light throttle BS on my
4runner (an aftermarket one cured it but only for 3 months then went to shit...OEM
is rock solid)



http://www.sparksparts.com/toyota/t...trol-scat/?part_name=throttle-position-sensor

 

For reference, using my Ultraguage on my '99 3RZ while NOT running, the TPS setting goes from 11 to 74 (no throttle to WOT).

Idling, the TPS reading is consistantly 9.8

Some time ago, I saw a TW thread on fixing the throttle to allow it to close all the way. I think he had to take apart the throttle and add (or subtract) a shim.

 

It is a drive by wire with the 4 pin TPS. The one in the link is the 3 pin TPS that won't fit. I believe the part number the 2004 needs it #89452-35030

 

While driving today with the scan tool connected the hesitation issue occurred and I pushed the gas pedal to the floor and the ABSLT TPS slowly started to go up. Over about 3 or 4 seconds the ABSLT TPS value went 14, 18, 22, 36, 50, 79.6. I think the throttle motor is worn out and too weak to move the plate when it is hot and any bit dirty. Any thoughts?

 

I took the air intake off and, with the key on so the drive by wire system is moving the throttle plate, the throttle plate clicks as I activate the throttle in one place with very low throttle. I think the gears in the throttle motor are worn out. There is no clicking with the key off and actuating the throttle plate by hand. The high pitch wine is coming from the drive by wire motor.

I guess the drive by wire actuator is in need of replacement or rebuilt. Any thoughts?

 

My 04 Tacoma does the same thing as you show in the video. It also has the loud whine. Mine has 150k miles and something in the drive by wire gives me intermittent issues. It only acts up during 90+ degree weather though and never gives me trouble in the winter.

 

I took the whole throttle body apart last night. I adjusted the closed stop on the motor side to allow the plate to close all the way. There are two closed stops, one on each side, they are the small set screws with locking nuts on top of the throttle body. I think this will stop the clicking sound since the gear backlash should be gone now. The actuator motor didn't appear easy to rebuild, but I will look at it again tonight.

 

Keep us posted. I don't want to buy a used TB just to have the problem show up again later, but I also don't want to pay $800+ to buy a new one.

 

the drive by wire actuator does whatever it is gonna do

the TPS tells the computer what the drive by wire system is actually doing

the motor for the throttle can be absolute crap , the TPS cannot be. they work together

 

I spent all evening taking apart, putting back together (several time) the throttle body and drive by wire system. I believe what is happening is the mag clutch is slipping and causing the motor to have to turn more than expected to move the throttle plate. The back of the friction plate for the mag clutch is missing a lot of little chunks of metal and end engaged with 12 volts it only holds the gear with a little force, not near what I think would be required.....this is all speculation as I don't have specs for any of this.

In my efforts to fix the issue I think I broke it completely. It will work once and then set an error code of either P2111 or P1126. If I clear either error and restart the car, then the engine will idle nicely and after about 5 seconds set once of those codes. I am sure the throttle is not "stuck open" because the idle is very smooth at about 650 rpm. I am going to try and get just the actuator motor and clutch assembly tomorrow and see it replacing those fixes it.

The scan tool shows the TPS reading correctly the whole time the engine is running.

 

I ordered a used throttle body from a local parts yard for $275. It will be here Friday.

 

Have you worked out the new throttle body?

 

Wrong throttle body showed up. They are replacing it with the correct one and it should be here Monday or Tuesday.

In the mean time I took the thottle control motor apart and found the mag clutch was very dirty and missing chunks. The mag clutch didn't hold well when energized. I think it was slipping so I sprayed it out with air and electrical cleaner. The truck now runs great for a few minutes then check engine light comes on and there is a full failure of the drive by wire system with either a p2111 or p1126. I probably shorted or broke a wire while cleaning it.

 

Again, for the third time, the wrong throttle body showed up at the yard that was trying to order it for me....so I went to the local LKQ and found a 2002 4runner. They charged me $44.06 for the throttle body and $3 to get in the yard. I put the used one from the 4 runner on last night and it is running great. No hint of any hesitation and feels like more there is more power, but I am sure the more power part is psychosomatic. If the problem come back I will post anymore work I do here.

 

Curious if the replacement TB worked OK?

 

Since the replacement 4runner TB the truck has run great.