so I own a 1990 JDM TII with very little after market parts:
- 2way LSD
- coilovers
- bov
- clutch kit
- high-flow cat
- turbo timer

Now i receintly went to a rx7 shop because of my car problems which were:
1) Stalling
2) Slipping clutch
3) Failed aircare (BC, Canada - emissions inspection)

It was found that my TPS was done and needed to be replaced, and a new cat, and clutch kit (ACT HD plate, SS disc). My car now passes aircare, and doesn't stall AS MUCH.

i.) If i'm in neutral not moving, at optimal temp, and i rev up the car and let it off the throttle never touching it again, my RPMS will drop below idle point and sometimes so low that it results in a stall. Especially if i'm braking then putting the car into neutral the rpms will drop to stalling point. I can prevent the stall by manually making sure my rpms don't drop if that helps.

ii.) When sitting flat in neutral/gear w/e, and i depress the clutch pedal, i can hear a clicking noise. bearings?

The shop doesn't know what is causing the stalling, they and I believe it is eletrical. When braking im not possitive but it feels like the power steering is cut a bit. Any action involving electric current easily causes my idle to change, for example brake lights, window switch.

Any input helps thanks.

 

i have almost the same problems... clicking and stalling...

 

if it doesn't stall, does the idle even out quickly to 750? Sounds like a vac leak...

 

i was told possible vac leak before and i mentioned it to the tech, i assumed he checked for leaks. i checked n e external leaks.

 

pressure test for vacuum/boost leaks first (much better than a visual check). You can make a tester out of hardware store parts or buy something like the one at www.boostpro.net/prodtester.html (universal tester) . I would do the idle setting procedure in the FSM. Then you can also adjust the dashpot, which is a damper on the throttlebody that keeps the throttle plates from snapping shut on deceleration. All that stuff can be found through searches on this forum and by downloading the factory service manual, the location of which is in the FAQ.

 

BAC. Do a search.

 

Why did it fail? Too much NOx, too much hydrocarbon?

 

i'll search up on those things thanks, any other possibilities?

 

too much hydrocarbons

 

if it is too much hydro carbons... i'll do the water clear test this weekend. my cars been locking up on cruising and when i stop at lights or so on. its fine when it starts p but dies later...

 

I don't have a BAC and my car idels at 700 rpm lol

but really sounds like BAC

 

what's the diagnosis on the bac? on my thread, someone said check my dash pot.. can that be the problem too?

 

I have the same problem, and I'm sure it's the BAC, since the screw on the side doesn't do a lick of good to the idle.

 

dont know why, but last night.... i was driving it home from work, and i believe it went into a limp mode. the first i've seen, it wouldnt let me rev past 2000RPMS in gears. so i pull my car over and my friend and i are checking out for leaks, and so on. after turning off the car, i hear a clicking noise. it seems like the bac valve, and i take a screw driver and place the tip to the bac valve. and ear to handle, yep... its the bac clicking but why does it do that?

 

For LIMP mode, do you know that the OMP is in good working order? I didn't know the BAC threw the car into limp.

 

no omp, been eliminated... but it seemed like a limp mode.... i couldnt rev up past 2000 rpms. it was like there was a limiter. i couldnt go any faster unless i kept shifting up, that is until 5th gear. i suspected the final gear would let me get away with 50mph-55mph, but i wasnt going to be doing that on a 65mph highway home.

 

Just FYI: I never said the BAC could make the engine go into LIMP mode. I said BAC because in the first post, the thread owner said he lets off the pedal and the rpms drop to very little.

IF the idle had been set right and the BAC was functional, then the BAC would not have let the rpms drop to nearly nothing.

 

What RPM are you idlilng at. I'm sitting at 500, with my not so working BAC.

 

hey, is the dash pot right after the TPS? cause i think the previous owner eliminated it... i see some epoxy.

 

No. The damper for the double throttle mechanism in that location. The dashpot is on the aft part of the throttle body, near the water thermowax area.

 

oh ok... whew... i thought i was outta luck. i'll recheck it when i get the time. been working too much... hopefully its worth the pay.

 

which bypass valve is on it? sometimes if the spring pressure is too low it won't close quickly enough and will let in unmetered air causing it to stall.

 

ok guys, my bac is clicking when the engine is at operating temp and shut off after a while. what am i to do?

 

I was having the same problem. i think the clicking is a relay, but the car doesn't do it now. here's what i did...

I adjusted 3 valves.
1. one is on top of the passanger side wheel housing. R = rich, L = lean. I leaned it about about until it died, then brought it back up. turns out it was all the way rich.

2. the screw on the top of the intake was all the way one way, turned it the other until it died, backed up half a turn then started it again and made more adjustments there.

3. then finally the screw that is on the throttle mechanism (im not good with all the names of these parts).

 

The BAC has a duty cycle. It constantly cycles at approx 120hz. If you put a load on the engine, say turn the headlights on while idling, the duty cycle increases and lets more air in to keep the idle up. The rpms might drop a bit at first when the headlights are turned on, but they should go back up right away due to the BAC taking up the load.

The BAC is for idle control. It does not have much of any effect if the *idle* is at say, 900rpm.

IF your engine is HOT, and idling, you might take the plug off the BAC and see if the idle drops or not. If it drops when you take the plug off, you know it's been working.

When you set the idle of the car per the FSM, you install the Initial Set Coupler. Doing that puts the BAC at a SET duty cycle, so that when you make adjustments to set the idle, the BAC won't be tring to messing with you by adding/subtracting air duing your adjustments, which would drive you crazy.

The BAC also goes and stays full open (no duty cycle, just wide open) if the key is put and held to START.

And if your setting the TPS and hear a click or two, it's either the Relief or Switching solenods coming and going. What your doing when setting the TPS, is setting when the Relief and Switching solenoids activate. Look at your wiring diagrams and you'll see that the GREEN TPS connector has two of it's wires also spliced to the Relief and Switching solenoid. Those are gnd wires and the gnd is put on or removed from those wires by the ECU. If you adjust the TPS to output one volt dc, then the ECU in turn puts a gnd on the Relief solenoid. Hence the click of the solenoid. That's basically what your doing when setting the TPS using the light method mentioned in the FSM.

Here: read this. It explains the BAC a bit better, though I don't believe you have to jump thru the hoops they suggest to figure out if the BAC is working or not. http://www.teamfc3s.org/info/articles/idle.html