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Discussion Starter #1
My throttle position sensor is no longer getting power, and I cant find a fuse or relay for it? Does it even have a fuse/relay? Or would it be one for the ECU? I checked both the main fuse box under the hood and the one inside car under the steering wheel, and all the fuses are good. And if the ECU relay was bad, wouldn't there be a lot more components not working??
I dont have much experience with this, it's my first project car, and I'm stuck.

I followed the wires to the wire harness and followed until it goes into the firewall behind the glove box. I removed glovebox and now I think I might have figured out which wires they are, going into the ECU box, but I'm not sure what to do now.. If anyone can point me in the right direction, I'd super appreciate it!
 

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Drivers foot (left) side fuse panel there's a power relay there (at least for a 85/86), use a large paper clip to insert to reset
 

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There's a jumper E1 connector on the engine harness under the dash on the later cars that supplies part of the circuit
 

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Discussion Starter #4
SilverMK2, is that one of the yellow convectors going into the ecu box? And so what am I supposed to do? i check each wire to see if they all have power while the engine is running or just while the key is turned in ignition?

AJ, is the relay round with a flat top? And is the hole in the top of the relay? If so, I think I found it, but it didnt feel like I hit a reset button or anything when I stuck the paper clip in..
 

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Yes, make sure its plugged in. At least in 85 E1 pin 9 feeds 5 V from the X connector on the ECU to the TPS and water temp sensor. There are a few other things on that connector like cruise control and water temp gauge.
 

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Your not saying if the car runs or just cranks. The TPS wires go directly to ECU. So try the following.

When you tested for no power with ignition on with TPS disconnected and center pin (red wire) showed no battery voltage on harness , then check at ECU pin 4 large connector. If no power then check 15a EFI fuse its ECU power source. Check 7.5a IGN fuse also.
 

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Discussion Starter #7
82TURBOSUPRA, so I just got the car running a few months ago, and it was driving pretty smooth for a while. Now if I try to drive it, each time I shift to a higher gear the tachometer fluctuates up and down as the car jerks back and forth. It seems to go away once I ease up on the throttle until I'm just very lightly pressing on it. While I was trying to narrow down the possible causes I noticed the TPS connector wasn't receiving any power. I only have the general TSRM for 79-92 and was super confused with the wiring diagram..
Only just last night I found an 82 specific EFI wiring diagram and it's starting to make sense. And your instructions just simplified it way more, thank you! I'll post again soon with my results.
The only other thing I'm having trouble finding in these diagrams is which ground point does the TPS/ECU connect to? Or is it the EFI fuse the ground point?
 

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Ground for 82 TPS is at the ecu. You can test voltage back probing pins 4, 5 and 6 to pin 8 (white/ black stripe) or a good ground point. Need to move throttle to test for open. If voltages are not there open ECU and check for bad solder joints for those pins to board and any burnt resistors and replace. 82 TPS wiring not the same as 83 to ecu. You might have to adjust the TPS once power is corrected.
 
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