Throttle voltage at ECU

[nix300zx]

What should be the standard volt reading on the throttle wire just before the ECU? I have tried to find this online and most have said .45V closed throttle and 4.5V open throttle. Mine is reading 30mV closed and 60mV open. I just recently installed an Apexi Air/fuel controller and it is unable to pick up the throttle signal at all.

What is the reading suppose to be? and what would be my first steps to fixing this? Also i do have a new TPS installed. The voltage going to the "gray" connecter on the tps was reading 3.75V.

Thanks

[Ace2cool]

That's correct information. .45V closed.

No clue what it's supposed to be at the ECU, though I would imagine it woudl be the same....

[nix300zx]

Thanks Ace, that is what I figured too. It has been running a bit rich and seems to have hesitation to sudden throttle change. I have a list of mods on my car, and this week I plan to have the ecu tuned for the list I have. I'm hoping this clears my problem. If I still have a low voltage and throttle hesitation, I will do a resistance test from the tps to ecu to make sure I have a solid connection. If I don't then ill know its in the harness somewhere. Could I bypass the harness and run a wire straight to the ecu? Or would that effect other things? Thanks again, this has had me puzzled for a while

[Ace2cool]

I'd double check to make sure it doesn't tap into anything else, but I'd imagine it would be fine.

Just to make 100% sure, you are testing the TPS, and not the ATS, right?

[nix300zx]

Yes I was testing at the throttle position sensor. As a note, I replaced the sensor a couple weeks ago as well.

[Ace2cool]

Cool. Yeah, just check the resistance between the sensor and the ECU.