I recently check the pressure coming from the air pump in my 87 N/A to see if the pressure came at a constant rise, and at 3k rpm the pressure was a constant ~3psi. However, at 4k rpm, the pressure rapidly rose and fell from 4psi to about 1psi numerous times when holding the throttle at a constant 4k rpm. Is this normal?

 

well i realized that this was a result of pressing gently or releasing the throttle to keep it steady at 4k - when pressing, the air pump generates pressure, when not pressing on the pedal, even though the engine is at 4k rpm, the air pump will barely generate pressure.

 

AT 3800 RPM the ACV dumps the air from the airpump into the silencer in the right front fender. That might account for the pressure drop.

 

oh ok that makes a lot of sense. does the pressure return to what it was at before 3800? im trying to do the air pump aux port activation modification and its quite a hassle...

 

It should. How much before I can't say off hand.


There are time, most of the time by the way, when your driving at a steady speed on the hwy for a time period over 60-90 seconds, when the air is dumped into the left fender even when the rpms are below 3800 rpm.

You can prove this to yourself by attaching two leds of different colors to the green TPS check connector and observing them as you drive under all sorts of driving conditions. You'd have to run wires long enough for you to see the led's while driving.

 

Is there anywhere I could find a definitive explanation to the mechanics of the air pump? I want to find out exactly how and when it dumps air. Thanks!

 

http://wombat.sevarg.net/RX7/RX-7_Training_Manuals/

The Fuel and Emissons download. Page 58 or there abouts.

Frankly, the BEST way to tell is to get some wire and two LEDS lights and run them to your wipers and tie them there. Other end connected to the TPS check connector. Buy two colored LEDS. Make them Red and Green to match the LEDS in the FSM for easier ID of what solenoid is opening and closing.

That Fuel and Emissions pages will help, but the most definitive method of finding out when the Relief valve in the ACV is dumping, is to observe the LED's on the windshield.

Same two wires could be run from the ECU but for a quick and dirty install, just running the wires loosly from the green check connector does fine.

There was a time long, long ago that I thought that the thing dumped only over 3800 rpms. Like I said, a long time ago. Experience observing the LEDS attached to the green TPS check connector straightened me out in a hurry.

 

When you made that check light setup HAILERS, did you find the connector for it or just tap into the wires that go to the check connector plug? Also, do you have a schematic (or a link to one) of how you wire that up?

 

On a Series four non turbo the TPS check connector is colored GREEN.

It's located on the right, fwd side of the engine bay.

It has three sockets. One wire in that plug is BLACK/WHITE and is 12vdc pwr.

Another wire is colored Blue with a Yellow stripe. It is also spliced to the Relief solenoid.

The third wire is colored Blue with a Red stripe. It is also spliced to the Switching solenoid.

If you have two LED's from Radio Shack for about three bucks, you just tie the Red wires on the LED's togeter and put a spade terminal on the end. The install a spade terminal on each of the other two wires.

You plug the red wires into the socket with the Black/White wire. The the other two spades into the other two sockets on the Green TPS check connector.

Then you start the car and warm it fully up. When thru warming it up, the LED that goes to the Blue/Yellow wire in the green check connector, will be lit up. The other LED will be off.

This is nothing more than the TPS lights that are used to set the TPS.

The only thing I did was grab some spare wire and extend the length of the three wires so I could tie the outfit to my wipers so I could see when a given light was on or off.

IF the LED that is going to the Blue/Yellow wire in the check connector is lit up, then there is no air being dumped out of the ACV. Any time it goes off, then air is being dumped from the ACV.

You cannot read the FSM and determine when the ACV is dumping the air into the right fender.

It's best to get LED of two different colors so you can distinguish one from the other.