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So, in my previous thread I've established that the Airpump has 12v, and when my tech grounded out the connector, the pump kicked on.
Today I decided to take a look at the relay. I was worried about damaging it before, because it was very reluctant to un seat itself from its box. By a chance of fortune (or misfortune maybe) when I was attempting to pull it out with some long plyers because I do not have a relay puller and my channel locks are elsewhere at the moment, the top of the relay came clean off, allowing me to see the insides. From what I can tell, they look pretty clean, but I have zero idea if theres an issue with the relay or not.
I did notice that if I manually actuate the relay myself, the airpump will kick on, and as soon as I let go, it turns off. Photos for reference:
It's difficult to see, but in the first photo, that is how the relay sits "normally" with the airpump off at idle, those two circular points are contacting one another. In the second photo my finger is separating the two contact points, and that is when the air pump engages. Would this point to the relay being bad?
could be the relay itself yea or it could be whatever triggers the relay isnt working. its easier to swap the relay. you can swap it with another one from that same fuse box and see what happens. if that doesnt work then youre going to have to chase wires. should be pretty easy to figure out since everything works. just make sure that each prong in the fuse box is doing what its supposed to. if its not, then look at the wiring diagram and figure out why.
could be the relay itself yea or it could be whatever triggers the relay isnt working. its easier to swap the relay. you can swap it with another one from that same fuse box and see what happens. if that doesnt work then youre going to have to chase wires. should be pretty easy to figure out since everything works. just make sure that each prong in the fuse box is doing what its supposed to. if its not, then look at the wiring diagram and figure out why.
The extra relay is (surprisingly) absent. The Radio relay. Odd thing is, my radio works. Looks like I will have to buy another one.
Edit: Apparently, according to the FSM (at least on US Spec RX-7's) the relay is for Bose equipped models only. That would explain its absence.
Last edited by SwappedNA; Mar 11, 2022 at 01:35 PM.
I doubt that relay is bad. They only really go bad if the relay box is hanging upside-down and they get full of water and rust out.
As stated it's most likely the signal to engage it.
But, since you have a PowerFC and a mid pipe there's zero reasons to run that air pump. The ONLY thing you need it for is if you are on a stock ECU or you are trying to pass emissions.
Go into the PFC Commander, into the Etc. menu, Function select, turn O2 feedback off. Car will drive great.
I doubt that relay is bad. They only really go bad if the relay box is hanging upside-down and they get full of water and rust out.
As stated it's most likely the signal to engage it.
But, since you have a PowerFC and a mid pipe there's zero reasons to run that air pump. The ONLY thing you need it for is if you are on a stock ECU or you are trying to pass emissions.
Go into the PFC Commander, into the Etc. menu, Function select, turn O2 feedback off. Car will drive great.
Dale
I thought even with the PFC you needed the airpump to regulate idle? Unless I'm wrong on that one (which I could entirely be).
The air pump is really only needed with the factory ECU and when using O2 sensor feedback.
The stock O2 sensor is in the pre-cat just off the turbos. Some air pump air is injected into the exhaust manifold and this fools the O2 sensor. The factory ECU compensates for this, it knows to "fudge" the O2 sensor's output when the air pump is on to get a correct reading. The PFC does the same. With the air pump not working you have a rough idle and on/off throttle is rough. Idle, cruise, and light load is the only times the ECU uses the O2 sensor.
The PFC does the same thing but you can disable that feedback. Then you just run off the fuel maps without the O2 sensor giving any input. Remember, this is a narrowband 1980's tech O2 sensor, this isn't fancy.
Just disable it and you will be good. You will also get the same fuel economy as before. I typically get 22mpg highway on my car - this won't affect MPG at all.
