88 crx DPFI 1.5L

So i had thrown a code 7, and the idle and acceleration were unbearable. Code 7 is the TPS, so i ordered a new one and went to install it today. Outside of the fact that this is one of the most bullshit things ever to replace, I got all the lines and hoses reconnected and started it only to get a 3000 RPM idle, and after a trip around the block code 7 came back. I know the TPS needs to be calibrated, as well as the base idle needs to be re-set (especially since i put in a brand new $250 IACV today). I measured the voltage from the red wire (signal) to the green (ground). Closed gets 0.04V and WOT gets 0.07V. I had my meter set to range 20 DCV. When im in that mode battery voltage appears as 1x.XX (12-15) Volts and ELD voltage is 4.XX volts (5). Basically this is saying my range is waayyyy low. What the hell? Is there not enough juice coming from the computer to run this sensor? I tested the yellow wire (power), which is supposed to be 5 volts, and I was only getting 0.07V, the same as the WOT value with the meter on the green and red wires.

I'm assuming there is an issue with the wire coming from the ROM to the TPS, but these symptoms just happened out of the blue two days ago. I already have my TPS plug green wire shorted directly to body ground (not ECU ground, read service bulletin for more info), and my ground on the plug is solid, but I'm not sure if the yellow wire is carrying enough voltage.

HELP!

Also note, that in the two minutes before the CEL kicks on after intitial startup, the throttle behaves mostly normal again, quick to respond to the gas, holds engine steady at various RPM under partial throttle, revs to redline when floored. But for some reason my values measured at the TPS connector are not what I was expecting.

Yeah i just drove almost 8 miles stop n go and highway, all feeling perfect, before the ecu popped the cel for codes 7 14 and 20. I replaced tps and iacv yesterday what the hell?

 

Do you have 5v at the MAP sensor? The 5 volt feed for both comes from the same place, the ECU.

 

Will have to test that. What happens if theres no 5v to either?

 

Check if the wire is shorted to ground. Check back at the ECU to see if it is coming out of there but getting lost in a break in the harness.

 

Also, where is this map sensor? My old camaro had it mounted on the firewall but my old civic had it on the TB. Which wires to measure volts?

Also if my map sensor wasnt getting volts wouldnt that throw a code and cause rough idle? So assuming it IS getting volts, then couldnt i trace the tps hot right out of the ecu and tap into it and create my own direct lead from the brainbox to the tps connector?

Bump

 

There's a "Y" splice in the harness where the hot +5V wire from the ECU branches to the TPS and MAP.

 

Which wire going into the ecu would i test for HOT 5v that leads to the tps?

Bump

I removed the three wire plug from the map sensor and there is 5v from the red/yellow wire to ground. What next?

Also when i tested this time i verified 5v at the tps. However, when i plugged in the tps and put my multimeter on the signal wire i got 4.48v with closed throttle, and no amount of adjustment would fix that. Also, at WOT i get 0.12v

I reversed the yellow and red wires too, and the same situation occurs. 4.5V at close, and 0.1V full open

 

you calibrated tps off the car on tb with multimeter, right?

i did this when i swapped on my JDM ITR throttle body with new tps and had 0 issues.

 

calibrated mounted on tb in car. I dont see why that would make any difference

Bump

ttt

 

is the new TPS specifically for the DPFI engine? the DPFI and MPFI are different because the throttle rotates in the opposite direction - have you tried switching the Yellow/White and Green/White wires? the Yellow/White is the 5V signal

 

Yes i checked the part number. Its definitely a dpfi tps