Hey everyone. My FD has 55k miles on the stock motor

To start off my FD has been losing power very slowly for the past month. When I got the thing it ran good strong no problems. One day I was revving it and the belt started to fray nothing bad. Just smelled.
Recently I havnt been getting to much boost maybe 5 at the most. Its set to about 12. Not much power at all.
Now I took it out to home depot maybe 10 miles away and when I left my house I noticed it really wouldnt go anywhere. I tryed to just drive and the thing would just creep along. Now im revving it to about 5k in first to make it go forward and it just seems like it doesnt want to move at all. just slowly creeps till it gets going. But it does this in almost every gear. It goes but takes a hell of a long time to get moving.
Now to the question. Is it the belt that has been fraying? The motor itself? Or the Battery? that is causing this.
I think the motor is giving up on life. I just hope it isnt too bad.
Any help from anyone is appreciated

BTW The rx7 motor is stock with just a exhaust going strait back.

 

So you've been driving around with a bad belt? Not good.

Please list your mods. What does exhaust straight back mean? Does that mean you have a cat-back or does that mean you have a cat-back, downpipe, and midpipe? Do you have a boost controller?

Sounds like you have the symptoms of a clogged cat or a boost leak.

Have you searched for a boost leak (checked couplers/pipes for splits, unattached vacuum hoses, etc)?

 

Could it possibly be a bad slipping clutch? U said you had to rev it to 5 k to get it moving, thats just a thought.

 

Hows the idle, and more importantly, hows the vacuum at idle?

 

I have seen quite a few rear main seals go out and cause the clutches to slowly give up. Recently replaced a 93 R1's clutch for the same symptoms.( had to wait a long time to start moving.) However once the new clutch was in I found major boost issues.( spiking like a bastard!)You can look in the inspection holes on the bottom of the transmission and see if there is a lot of oil on the clutch assembly area. Good luck. Dave

 

My idle loves to jump around from 1.5k to 300 and sometimes stalls.
I have a Profec B and my exhaust is just one pipe all the way back. No Cat no Pre. My AC doesnt work all the time. I have to put it on 4 just to blow, but no cold air comes out. 1-3 doesnt even blow.
Im thinking its my clutch. With trying to get it going. Only thing is it just happened out of the blue. No signs of anything.
I do think something is wrong with the turbos too. They dont seem to be running very strong. Maybe a vacum leak?
Thanks for all the replys. Any Ideas anyone?

 

turbo's gone maybe, how slow is slow?

 

So you were running 12 psi with a full exhaust on the stock ecu? NOT SMART.

Time to get a compression check....your motor may be toast. Then again, with all the other problems you are experiencing, it may be something else.

 

Isnt 12 Normal? Im sure the motor can take 14 psi. Im also sure the engine wont pop just cus of an exhaust mod. Its been running fine for 20k miles with the exhaust.
Enlighten me why the stock ECU needs to go just because of the exhaust and the 12 PSI. All the exhaust would do is alleviate back pressure right? Plus it would get those hot exhaust gasses out of the engine bay. Not to seem mean or pompous just asking.
Another thing is that the damn ProfecB instructions are in Japanese.

Doesnt seem like compression. But im not sure the how the rotory will act under compression failure.
Well hard to explain slow. Seems like its running as fast as my corolla when the rx7 gets up to speed. My corolla is 1.8 DOHC 7afe. Just seems like the turbos are spooling but just doesnt seem like its getting power. I was playing with the Profec but still dont totaly know how to tune it.
Is it possable for turbos to spool and not compress the air? I dont know im just thinking of anything.
Not in any rush to fix it though. Thanks for the help guys, Any more Ideas?

 

the moter is very able to take 12 psi, however the computer cant compensate for higher boost, This causes the car to run lean with lots of advance = popped engine.... 10 psi is all you can safely run on stock ecu... 11 if your lucky, some daring people have gone 12 :P

 

Lol I dont recall running lean though. Matter of fact I run very rich. Guess Im daring :p.
It seems to rev fine. Thing is this is my first turbo. So im not to well versed. I read alot so im kinda ok in that aspect.
I plan to take it to the shop and get the run down but still. I still think the clutch is the evil. But the turbos have been acting up. Any ideas how to check to see if the motor is blown?
If It was blown wouldnt it have problems revving to 8? Thanks for the quick reply

 

You'd like enlightening? Ok then.

RX-7's ECU's don't run on MAF sensors like many piston engine cars do, they run on fuel maps. That is, the ECU assumes it knows how much boost is going into the engine (based on throttle position, rpm, etc.), and at what RPM its coming in. The issue arises when you start to modify the car. Creating more airflow means the turbos spool faster. Getting to 10 psi (or, God help you, 12 psi) at 2300 rpms instead of the usual 2800 rpms means that you are running lean from 2300-2800 rpms. The ECU assumes it knows when you are reaching full boost, and adds in the right amount of fuel for what it "knows."

Running lean causes detonation which= blown apex seals and a $15k lawn ornament for you.

Lets say you somehow control your boost and with the exhaust mods get it to not spool until the normal 2800 rpms. Well when you get there, in your case you're running 12 psi. The ECU is only adding in enough fuel for 10 psi. This again = running lean. See above.

If you have been running with 12 psi on the stock ECU for 20k miles then you are among the very, very few who have successfully done so. And as you stated the motor can take 14 psi, in fact it can handle quite a bit more than that. The issue is the ECU, and its deathgrip on the fuel system.

That being said, I hope your motor didn't go. If it didn't, please take the advice of the forum and get yourself an boost controller at the very least, preferably an ECU that can handle your particular mods. If it did, then hopefully you'll learn from the experience and still get a boost controller, an ECU, or both.

 

Problem is, you can't be "daring" with the FD. You're dealing with a motor that depends heavily on proper air/fuel/ignition ratios for life expectancy. How do you know exactly that you were running rich? All motors are different; you could have had some circumstances that allowed you to run for 20K miles with no problems (boost leak, whatever...).

You'll know if it's the clutch. You'll be forced to rev the motor hard to get anywhere, and you'll smell it. A popped motor gives off a lot of different signals: poor, extremely rough, or non-existent idle, puffing smoke sometimes, hard to rev...it depends. To me, it sounds initially like you fragged your motor, due to poor knowledge of the rotary with regards to forced induction, but can't say for sure.

 

Like I said above in this thread I have to rev it high to get anywhere. I was talking to a friend, and his buddy had the same problem in his car and it was the clutch. Just my clutch seemed fine till today.
I have a autometer reading A/F, even thought autometer isnt the best, im sure its not off big time. Another thing is I can smell fuel when the meter is running rich. So im sure the meter is right when it is saying it is running rich. I do have a poor idle. But I have had that since I bought the car.
Only smoke I see is at start up. Just alittle bit of white smoke, but isnt white smoke at start up mean it is just dismissing some oil that was shot into the rotor housing when the car shut off?
Now with the small knowlege I have. Wouldnt retarding the timing make your car run richer meaning you can boost higher? Because advancing makes you run lean? Maybe that got me 20k without running into breaking down?
Thanks for all the info you guys. I do intend to make sure it is done right. Just want to make sure the guy is competent. Plus I dont want to make anymore mistakes

 

Your A/F ratio gauge runs off the stock O2 sensor, which is about as useful as a knife in a nucleur bomb fight. Do not trust it. Find a local dyno and borrow their wideband O2 sensor and test your AFR's for real. Or if you have the cash, get a wideband with a digital readout installed in your car. To be safe your AFR's should be in the 11:1 range. I can all but guarantee you that they aren't if you have 12 psi on the stock ECU, unless theres some serious fuel system malfunction going on.

Can you further describe your "poor idle?" And more importantly, what are your vacuum readings at idle (thats the "other" side of the boost gauge ). On a healthy motor the readings should be between 14 and 19 in Hg, but more importantly they should be stable. This is assuming that the idle is stable, so if it isn't, the test doesn't apply.

The best thing to do is to get a compression test just to make sure the motor is healthy, then go through everything to find the issue.

 

Start the car in the morning when it is cold and wait till oil circulate the whole engine and turbo. Then take it out for a spin and see if you notice any difference. If the cars pulls strong like when you first got it , then it is 100% a slipping clutch. Because when your transmission gets hot it'll cause your pressure plate to lose grip and won't grab unto the clutch as much as possible. So if your car pulls strong when it is cold and creeps slowy when it gets hot then it is the clutch.

 

Take your car to a ROTARY shop and get a compression test.

 

Last time I looked it was around 18. i just went outside and let it idle and it was like 19. All stable.
I tryed to take it out for a spin. It didnt want to move. I put it in reverse and tryed to back out, it just creeped and I was revving it to see. It was just a hassle to get in back in my space. But It wasnt this bad earler.

 

Sounds like your clutch is toast. Nonetheless, get an ECU upgrade before you finally roll snake eyes and pop a motor.

 

check the spark plugs first.

 

I plan to get a new ECU, and I do need new sparks.
Well thanks for all the help guys. Learned alot Ill be sure to update when I get this solved.