1jz map sensor voltage

[durangosc]

I just finished a soarer 1jz swap into my 98 sc300. The map sensor plug is missing. I think I plugged it in right but I am only getting 5v to the blue with red and 0 volts to the green with black. Can anyone tell me the order the wires plug in and also which wire is ground, 12v, and 5v? Thanks

 

[hvyman]

There 5v ref, signal , and ground.

If your looking at the back of the connector with the clip up blue w red stripe on the left, green/black middle and brown on the right.

 

[IBoughtASupra]

Let me add, if it is missing the ground, you have to connect it back to the ground off the ECU, not the chassis ground.

 

[durangosc]

Which wire is 5v?

 

[durangosc]

Also since I have one with 0 volts can I just run 12v to it?

 

[IBoughtASupra]

There 5v ref, signal , and ground.

If your looking at the back of the connector with the clip up blue w red stripe on the left, green/black middle and brown on the right.

Also since I have one with 0 volts can I just run 12v to it?

If it is supposed to be 5V, why would you give it 12V? Are you trying to fry something?

 

[durangosc]

I thought one wire is 5v signal one was 12v and the other was ground. My green wire reads zero with engine off and 2.xx when at idle, is this right? I just thought map was wrong because it won't hold idle very well. And it's running Rich at idle.

 

[seoul4korea]

I thought one wire is 5v signal one was 12v and the other was ground. My green wire reads zero with engine off and 2.xx when at idle, is this right? I just thought map was wrong because it won't hold idle very well. And it's running Rich at idle.

Our cars use 5V max for almost all of its sensors. One is a 5V ref line, one is a ground and the other is the signal like TOO the ECU.

Meaning it reads changes to the 5V ref line and sends the voltage to the ECU to let it know the reading it's getting. It will rise up to it's max voltage (Close to 5V), once it hits the Max voltage you'll run into fuel cut.

IF you want to get past that they have ways, on my 1j with emanage blue we monitored the MAP sensor output voltage and clamped it down before it hit fuel cut and then allowed the emanage to continue the fuel map and continue reading MAP sensor signal from the provided Greddy 2 bar map sensor.

 

[durangosc]

I have a CEL code 31, this is why i thought the MAP sensor was wired wrong. Could this code also mean vacuum leak, because thats what its acting like.

 

[ifyouaint1sturlast]

Did you verify that it's getting 5v and ground?

The ECU outputs a regulated 5v supply to critical sensors like the MAP, TPS, etc..

Not to mention there is also a specific ground on the ECU meant for it, not just any ground. You need to take a multi-meter and test to see that you're getting the right signals. No it will not give a code (from my experience) with the vac disconnected.

 

[seoul4korea]

Did you verify that it's getting 5v and ground?

The ECU outputs a regulated 5v supply to critical sensors like the MAP, TPS, etc..

Not to mention there is also a specific ground on the ECU meant for it, not just any ground. You need to take a multi-meter and test to see that you're getting the right signals. No it will not give a code (from my experience) with the vac disconnected.

What he said, I don't get codes either as it would just meter the outside air and try to adjust the motor for it.


Also do you notice a change in idle when plugging/unplugging your MAP at all? Maybe its just time for a new sensor.... I mean not to be a jerk but judging from your photo that motor looks to be pretty rough.