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Toggle Position Sensor put my car into permanent race mode

S

SeanP

New member
A bit of a long story so please bear with me. Two days ago the car gets sluggish, can't pass, can't go up hills, hesitation in the pedal.... So I'm thinking fuel delivery problem, maybe the CC. I turn the ignition on and pop the hood. The idle air control valve is madly clicking away. Click, click click......

So I deem that can't be good and I replace the IACV. The car is a bit better, but still its like driving through mud, and I still have the question of fuel delivery. Since it was time I put in a new fuel filter and test the fuel pressure. 45 psi at ignition, dropping to 39 or so psi when you turn on the motor. So the fuel delivery is just fine.

Next, I get an OBD scan down at the local auto parts store and the Toggle Position Sensor comes up. Like an idiot I don't get the code, but I get the sensor. I replace the TPS and now the car is in permanent acceleration mode. Throttle wide open all of the time. Makes braking rather interesting and its super quick off the line, but not the ideal case for family driving. My multimeter says the car is sending 5V to the TPS on the grey line just like it should with a small mV signal on the blue and black wires.

Does anyone know what is going on with this? Would a misreading of the pressure in the manifold cause the toggle butterfly to stay open forever? Can the butterfly get stuck? If other folks have other ideas I'm all ears.
 


Did you just slap the tps straight on? You have to watch where the little L bracket clip (term?) is and to make sure it's in front of its mating part. Slide the tps on at a 2 or 3 o'clock position and then turn it to align the holes.

I don't know all the terms for the pieces inside so maybe someone can clarify.
 
I had a VERY similar issue after my build. Reinstalled the TPS and when driving every time I left off the gas car would stall... I reinstalled correctly and fixed the issue.
 
Well the high revving came from the idle air control valve, for some reason it didn't fit properly or the computer didn't learn the first time, but after I loosened and tightened some of the bolts on the throttle body and re-seated the IACV the high revving went away. This morning I installed the TPS again, I do believe I aligned it correctly as mentioned but I am getting a PO122 error, low voltage to the TPS. The car idles at 800 rpm, just a low rumble, it has low, easy acceleration but no 'po' like it used to have. I am going to double check the seating of the TPS as soon as the engine cools.
 


I did something similar, with the car in ignition mode I pressed the gas pedal fully 5 times and then shut the engine off. I had misaligned the TPS fitting the first time, I had it dialed in, but not flush with the throttle body. Second fitting solved that problem. Car still has power problems though. P0300 was the latest error. Sparks and coils were just redone, fuel line pressure to before the injectors seemed to be fine.... so I guess it is the oxygen sensors, or CC..... I guess I will find out tomorrow at the shop.
 
The P0300 wasn't spark plug, or coil related...and it shouldn't be cause I just had new plugs, new coils, fuel injector wash and few other maintenance things done. And the P0300 code is confounded by two problems existing as once. My check engine light never came on, and my service engine soon light would come and go. The IAC went madly clicking away because one of the lines on its circuit was corroded. At the same time, or very similar time the CC plugged. I suspected the green wire going to to IAC as it had wildly varying voltage, but I couldn't find values for the voltages.
 
Let's keep in mind...new Bosch or platinum plugs can cause misfires almost as soon as they are put in. Same goes for a plug that was installed incorrectly and cracked or one that was dropped and cracked.
 
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