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RX-7 2nd Gen Specific (1986-92) RX-7 1986-92 Discussion including performance modifications and technical support sections.


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Old 04-15-2009, 09:14 PM   #16
WE3RX7
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without the OMP plugged in, you can still rev the car... just cant drive it...

I'm still banking on TPS issues or MAP sensor...






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Old 04-15-2009, 10:52 PM   #17
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What Ludwig said, is that I can rev it in the short range of the rpm, but I cant rev it in the "wide" range of rpm. Now, I already made up my mind that I'm not going to DGRR this year.

My chip will be here friday, I will install it, and run the car again, then post the results.

I think that part of the problem is all the adjustment screws on the Throttle body, like the thermal pellet and all that crap....


One problem I also noticed is that my BAC WILL NOT TURN OFF! I posted this before in a diff thread, but no one gave any feeback on that.

Is it possible I have a bad BAC that's contributing to this on top of everything? I will test it friday also, and post the results.
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Old 04-16-2009, 05:49 AM   #18
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Does the BAC make a sound when it won't turn off? I hear a small clicking/pumping sound coming from it after I re-installed my engine. It didn't do that before (and my idle sucked ass before).
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Old 04-16-2009, 03:11 PM   #19
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yeah, it just kinda "whirs" or whatever, non stop, sort of like how a loud fuel pump might wirl if it was continually turned on.

The thing is, this is with KOEO, so the motor is not running, why is the BAC still on, it did not do this before, you're right.
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Old 04-23-2009, 10:46 PM   #20
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Update:

Got the update chips, installed them, and had no connectivity with the PDA.

Installed old chips, car works fine, but still have OMP Fail code. (removed pump)

I THINK MY BAC BAD on top of this!!!!

All of you guys kept saying "sounds like a vacum leak" there you go! I mentioned that the BAC would constantly "Buzz" and stay on with KOEO (key on engine off).

The car ran a lot better when I unplugged the BAC, and I could rev now, but the timing is off.

In the RTEK, timing reads: (720~780rpm)

T-Timing: -5 degrees

L-Timing: -20 degress

In the FSM, it says timing should be that, but with positive values. When I lightly rev the car, the timing goes into positive.

I tried hooking up a timing light to the L1 wire, conected the "Check" connector to the car, and set timing... I think it still runs rough...

DTI is shipping me another set of chips, so when the GOOD ones come in, I will install them, and post a HD video of the engine running.

In the mean time, does anyone have a working S5 N/A BAC valve?
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Old 04-26-2009, 04:43 AM   #21
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Unfortunately, The BAC valve is not likely your problem... I am guessing that there is a wire crossed somewhere to the BAC. The BAC should be pulling air in through the AFM anyway, so it shouldn't be a vacuum leak.

The BAC is a solenoid and will operate when it gets voltage. I think yours is working just fine, but getting a signal when it shouldn't.

If you want to test it, apply 12 volts to it to verify that it opens (take it off the manifold and watch the plunger). If it opens when energized and closes when de-energized, it is working properly.

Your timing sounds just fine (I think negative indicates ATDC which is the factory spec).
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Old 04-27-2009, 12:31 AM   #22
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Well, I will check the solenoid, just found how to test the BAC in the FSM, so I will do that when I mess with the car next time.
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Old 04-28-2009, 08:19 PM   #23
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Ok, I tested the BAC valve, Ohms resistance reading on the car was 11.2, and the solenoid clicked when I applied 12v to it like it said to do in the manual.]

The UPDATE chip came in, I installed it, and was finally able to select "disable OMP" option on the ECU.

I am about to mess some more with the timing...
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Old 04-29-2009, 01:29 AM   #24
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Ok, so I still had the revving problem with the BAC plugged in. I unpluged it, and could actually drive the car down the street for the first time in like a year!

Right now, the car will stall out at a stop sign, or when I put it in neutural, it has low revs, etc.

Power steering works, brakes work but need bleeding, clutch works, but there is a whine when I let go of the clutch pedal. (Replaced the throw-out bearing so it might be the pilot or the transmission itself)

So, I need to fix this stalling issue soon, but other than that, the vert is almost ready to go!!!
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Old 05-01-2009, 12:37 AM   #25
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I almost got it!!!

Ok, so I was looking around, and decided to mess with the throttle body.

My "Fast idle cam" was way out of adjustment, at 75* it was between the 30 and the 70 mark. I got that adjusted, then adjusted the gap in the primary butterfly to .018"

After that, I plugged in the RE-Tested and cleaned BAC valve, and all worked great, my car could now rev with the BAC valve just fine, and ran better than my first outing.

My current problem: The engine stalls when I pull to a stop.... this is now with the Timing and TPS adjusted, and BAC plugged in and functioning.
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Old 05-01-2009, 12:29 PM   #26
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Did you adjust your idle fuel mixture yet?
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Old 05-01-2009, 03:17 PM   #27
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idle fuel mixture?

You mean the screw on the very top of the TB to set idle? yes

the idle is at around 700~800 right now, it doesnt stay exactly steady, but I tried to dial it in a bit.

I dunno, it runs ok at throttle, but it just stalls and the idle is weak. I think I might have a vaccum leak, but i think the big problem lies elsewhere.
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Old 05-01-2009, 06:53 PM   #28
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Ok, so with a LOT of searching, I managed to find that a possible cause COULD be the dash pot not being adjusted properly and my spark plugs being foulded a bit causing a bit of a fluctuating idle....

Interestingly, the dash pot and another two sets of screws on the TB are not even listed for adjustment in the FSM, I found that really odd, my Dash pot i think is a bit off, I was looking at it when I readjusted the fast idle cam.

I am wondering about the people however that completely removed their thermowax pellet and no longer have a dash pot...

My car starts, then idles at 3000, drops to roughly 1,400 rpm, and then it will idle if I dont touch anything, but as soon as I put the car in gear it dies.... when I start it back up, it will hold idle but it would be kinda weak. I'm wondering why it would die when put into gear with clutch pedal still depressed? I have a whine when I depress the clutch (new throw out bearing) so it might be the pedal being mis-adjusted too.

When I timed the car, the L1 wire lined right up with the mark, but it didn't quite line up exactly on the trailing side... but I did not adjust it for the trailing side.
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Old 05-01-2009, 11:02 PM   #29
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You might have something with the vacuum leak theory. Does the car misfire while idling or purr along? If it misfires, it is likely running lean (less than 13.5:1 at idle) due to a vacuum leak letting in unmetered air. Stock RX7s run very rich of stoich at idle.

edit: My '86 would start at rev to some insane rpm unless the shifter was left in gear, when it would start, rev to about 1500 rpm and then settle down to a good idle.

If I had to guess, I would say that your idle setting (reached by placing the car in gear when starting) is too low (not 700-800 rpm, like you think).
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Old 05-02-2009, 03:07 PM   #30
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Ok, I spreayed some Throttle body and air intake cleaner to test for vaccum leaks... could it be that TB cleaner is not as volatile as carb cleaner?

I could not find any leaks
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