So I bought the car with CEL on. Smelled like it was runnin REALLY rich, so I figured O2 sensor. Wasn't too concerned because everything is fixable and it had potential. Well I read it and it was the TPS. Pulled the TB, cut slots in the screws and took it off. Got a new one from Oreilly's and installed. Tried to check with multimeter and it shows 0.0 at closed throttle ALWAYS. No matter the adjustment. Shows max of around 3.9-4.1 FOT. Can't get it any closer to the dealer prescribed voltages. Is this another bad TPS or what? At first I was getting absolutely nothing, then I realized they spliced a wire from the O2 sensor to the ground on the TPS. I put that to a grounding spot and spliced the wires back together on the TPS ground and that's when I got the readings described above. I don't see any other issues with wiring. Input to ground, I get 5.5 ish, more than enough. But with the output it's giving the other. I'm at that point where you get stumped and irritated and take it to the shop. Just thought I'd see if anyone had any ideas.

 

BTW, it's a 93 CX, D15B7, headers and exhaust, and CAI. Other than that, stock engine. TPS readings were taken with car off and ignition on.

 

The O2 sensor and TPS do share a common ground wire (Grn/Wht). What two wires are you probing to measure the TPS output voltage? Post pictures of the TPS and it's wires.

 

Ahh... Is it necessary to have it grounded to the ECU or can it be grounded to the Engine ground point? Where is it normally spliced to the TPS? He had a T connector type set up and it caused the wire to break.

The Red/Blue is the return line correct? I'm measuring the Green white and Yellow White I believe they were. (Can't take pics right now, at work.)

 

bump... help?

 

also, note the d15b7 block with pm9-2 head. this isn't the stock for this car so it's been swapped. would that change anything with the wiring?