I have a JDM H22A swap in my EJ1 Civic ("EG coupe"). I've had this swap in the car for 11 years now, I had to replace my TPS twice in 2017, the 2nd one I used an OMNI and it worked fine until last summer, the car has been my daily since 2016. I was able to calibrate it without issue both times.

last August I was able to get closed throttle to 0.5 but WOT only up to about 4.1, this worked fine until here recently. I checked the calibration and it gave 11.3 V at closed throttle and then 7.7 V at WOT. Obviously these numbers are wildly out of spec and moving backwards. So I put in a new TPS to get the same wild crazy readings.

I'm honestly quite stumped here. Theres no way the wires spontaneously reversed themselves and I am definitely not mixing up the MAP plug as my map is on the other side of my intake manifold near the firewall.

My ECU is a chipped P28 I got from Phearable.net to replace my buggy JDM prelude ECU about 4 years ago in early 2017. Idk if my ECU is somehow causing these wild TPS readings or what.

Somebody please help!

 

Something is very wrong there, obviously. Check the outer two pins on the TPS plug, you should have 5v with the key on. Getting anything over 5v on the signal (middle) pin is not right at all.

 

On the yellow wire It says 7.1 V, this one should be a constant 5v. This time around I am using a new multimeter maybe it is faulty? It's a cheap one from AutoZone.
if that's not it then what in the heck could be making it do this?

 

those cheap aftermarket sensors wont work well

 

If it truly is 7.1v and not the 5v it should be, I would try swapping in a different ECU.

 

Check 5v reference at all the other 5v references. See if it's the same reading.

 

Thanks for this tip. I swear I'm not being lazy. I've spent a good half hour searching for other locations I can find a 5v reference, I get alot of MAP sensor threads in my search results.
where else can I find a 5v reference on an OBD1 harness?

 

MAP is a 5v sensor, see what you get on that plug.

 

The IAT is 5v too.

 

engine coolant sensor

if they all have the same out of range 5v ref then the ecu is bad