So, I've got a 90 RX7 TII. Engine was rebuilt about 12k miles ago. Runs great, 224hp 212torq no problems at all. I was driving somewhere for thanks giving and suddenly lost power. After further inspection I noticed a fresh hole with liquid gasket on it on the ACV. I think the bolts came loose and it popped off... I know I know......

The best I can tell form the Work Shop Manual is that it is an Air hose... it goes from the ACV to the Air Pump. I can not find anyway to order this hose or to really verify if that is the problem.. any suggestions?

 

Hopefully the FC guys know what you are talking about b/c I can't picture it. Take a pic if you can.

 

It's about 3 hours away from where I live at a buddys house due to where it broke down..

However you can see the part at: http://www.cochran-racing.com/FSM/s5...tems_turbo.pdf PDF Page 43 Part #4 The hose coming off and going to part #2. Also on PDF Page 61 the last image shows a close up of the hose and PDF Page 65 First image it is marked as #1 Air hose

 

The ACV is 100% emissions related, so it's not the cause of your power loss. The air pump hose can go missing and the engine won't know the difference. My first guess would be a loss of compression, so test that first.

 

It's not part of the emissions, it's part of the secondary air injector system, that hose that is gone, goes to an air pump, the other end goes into the ACV if you follow the manifold down to the block it connects after the exhaust system. The engine was rebuilt 12k miles ago and is solid. I was driving down the road and hit those grooves in the road, when that happened the metal cover that goes over the turbo (the metal plate, nothing special covers a lil of the exhaust as a protective cover) came off along with something else. It was fine til I hit the grooves in the middle of the road. I was accelerating to pass someone.

Also, it's running extremely lean when I start it, and I can't get that to balance out.

 

Yes, it actually is 100% emissions related. That's what the secondary air injection system is. Do a search of this forum for emissions removal, and you'll find that the air pump & ACV are very commonly removed. I do not have an air pump on my turbo car.

The air is injected into the exhaust ports & the catalytic converter to promote cleaner exhaust gases. The air from the pump never makes its way into the intake manifold.

 

So, even though the problem started as soon as that disappeared, it's not related? I couldn't find it on the road so I couldn't recover it

 

It's not possible for it to cause any power related problems, so it can only be coincidence. It is strange that it popped off at all really, since the air pump & ACV are set up to vent excess pressure. I guess it could have just broken down with age.

What are the exact lack of power symptoms? Any hard starting or is the check engine light flashing?

 

No check engine light flashing. To get the car to start I have to push the gas in all the way, and then it runs like crap, you can hear the sound being wrong, the boost gauge isn't looking the way it should for vac when it starts. If I try to drive it it has NO power, the turbo won't spool and it does 0-20 in about 30 seconds

 

Those are classic signs of a loss of compression. Been there, and it's not fun. You can do a quick and dirty compression test by pulling the EGI comp fuse & one of the trailing spark plugs. Crank the engine over and listen to the pulses. If there is an irregular pattern (ideal is 3 steady chugs per rotor), then you have a problem. Repeat by replacing the spark plug and trying the second rotor the same way.

 

Trailing plugs are on bottom right? Also I'm still trying to find the emissions post you mentioned

 

Trailing is the top plug, which will be easiest to remove anyhow.

Search thread titles only for "emissions removal" or something similar, and highlight the 2nd gen tech section. You can also read up on the emissions systems here: http://mazdarx7.iougs.com/emissions.shtml. Just keep in mind that this page is for NA cars, so there are small differences. Also there is one time air pump air goes into the intake, but it's only during decel via the anti-afterburn valve (AAV).

 

If it's a loss of compression what do I need to do? Rebuild it..?