Vacuum pump confusion

[MuRCieLaGo]

Hi,

I had a Code 61 for exactly 3 seconds this afternoon. So I tried to figure what is the problem.

When I put the key ON, I don't hear the vacuum pump. So tonight.

1st of all, I unplugged the vacuum pump and test the connector with a multimeter. Ground is OK, however I don't get any signal from the brown wire. I asked somebody to put key off/on while I read the multimeter, still nothing.

2nd of all, I opened that vacuum pump. What a mess! I don't think I can fix that now. It was full of rusty water.





So I put everything back on, I know for a fact that vacuum pump doesn't work.

I then went for a strong 10 miles ride, car runs like it should. Very strong at high RPMs. No SES light (erased previous Code 61).

Now I am very confused.

1. Why I don't have any current coming in the connector?
2. Why is the car running fine without the vacuum pump working?

[Paul Workman]

I do believe I have my pump that I removed when I removed the SPTs. It's yours, if you want it (and I can find it!!)

Paul.

[MuRCieLaGo]

Wow yes I'd buy it instantly. But I really can't understand why the car runs perfectly without it running...

I hate when I don't understand.

Thanks a lot Paul!

[RIP]

That vacuum pump isn't in use until the engine vacuum goes to almost zero. This happens at wide open throttle. Engine will run the same until you don't have vacuum to hold the 8 secondary throttles open.

[MuRCieLaGo]

Originally Posted by RIP

That vacuum pump isn't in use until the engine vacuum goes to almost zero. This happens at wide open throttle. Engine will run the same until you don't have vacuum to hold the 8 secondary throttles open.

But I gave the car a strong 10 miles ride afterward (multiple WOT pulls) without any problem...

[A26B]

The vacuum pump provides supplemental vacuum to the secondary port throttle (SPT) system. Vacuum is also provided from the engine during normal operation. If your SPT system is tight, i.e. no vacuum leaks, it will hold the SPT system open for a short romp. When you let off WOT, engine will again provide vacuum.

With vacuum leaks, SPT will not open at all or slowly close, depending on severity of leak.

[We Gone]

WOW.. Looks like water intrusion for sure. You may want to check all electrical connectors, clean and apply some dielectric grease to them.

[Gunny]

ditch the secondaries, get a new chip from Marc, problem solved

[MuRCieLaGo]

Originally Posted by A26B

The vacuum pump provides supplemental vacuum to the secondary port throttle (SPT) system. Vacuum is also provided from the engine during normal operation. If your SPT system is tight, i.e. no vacuum leaks, it will hold the SPT system open for a short romp. When you let off WOT, engine will again provide vacuum.

With vacuum leaks, SPT will not open at all or slowly close, depending on severity of leak.

But I swear it doesn't run at all and I have done at least 8 WOT runs until 7k RPM and there's no issue. I thought that in these conditions the ECM would block my RPM to 3k...

Originally Posted by We Gone

WOW.. Looks like water intrusion for sure. You may want to check all electrical connectors, clean and apply some dielectric grease to them.

I knew there was something wrong when I opened it and it was full of rusty water...

Originally Posted by Gunny

ditch the secondaries, get a new chip from Marc, problem solved

This!

I own a RX-7 and I removed a lot of systems. Made everything easier.

I would like to remove that secondary system.

[Dynomite]

I am the Contrarian here

I love the Secondary System operating and it is very easy to maintain if you block TB Coolant at the Injector Housing ending up with the 10 minute Plenum Removal.

I really like the FULL ENGINE POWER light on the panel on the 1990s. On the 1991 you only have the green tiny light by the Full Power switch which on my 1991 I have eliminated the secondaries

because...because on the 1991s they eliminated the FULL ENGINE POWER light on the panel