veedubbed

I have made several threads on my problems, but have yet to get a response to anything. I'm going to compile my list of what happens in detail, and what I have tried. This car is driving me crazy and I'm tired of screwing around with it, only to get nowhere.

Here is my car -

87 TII
Emissions removed
Air bypass removed
TB Mod, no thermowax system
550cc primaries, unknown condition. They have 115,xxx miles.
690cc secondaries
3" turbo back
FCD
TPS set dead on, reads 4.63K ohm at WOT, 1K at idle. No dips or dead spots in the sweep.

*** The previous owner of the car has screwed around with the screw in the AFM. I have no idea where the hell the screw is supposed to be set ***


1. Cold start

- When I start the car cold, it does not matter if I start it in gear or out of gear, the idle goes straight to 1500 RPMs. While it is running at 1500, it sputters/mifires/pops like there is no tomorrow. After ~2 minutes of running, the idle will come down to 1100 RPMs, where the misfire almost goes away, but it will continue to sputter/misfire/pop every 10 seconds or so.

2. Driving before warmed up.

- If I am driving the car before it is 75% warmed up, it will not idle. Say I come to a stop sign, and cluch-in, the RPMs drop and the car dies. It does not make any attempt to stay running, just dies.

3. Idleing

- After the car is warmed up, it will continue sputtering/misfiring/popping every 5-10 seconds. It is not bad, just enough to be annoying, and take the smoothness out of the idle. If I jump the initial set, the idle drops immediately to 400 RPMs, and sometimes stalls. because of this, I cannot set the idle worth ****.

- If I turn on any accesories, such as the lights, heater, etc. the RPMs will drop and take a second to come back up. When I stop at a stop sign or stop light, and clutch-in, the RPMs will drop to 1000 RPMs for a second or two, then fall to 400-500, and then it slowly comes back up to 750 RPMs. I have cleaned my BAC several times, to no avail. It gives a strong click when ground/12v are applied to it, and measures 11.9 ohm resistance.

4. No-load misfire

- If I am sitting in my driveway, car in neutral, and hold to revs between 1100-2000 RPMs, the car will have a rapid sputter/misfire/pop, identical to the cold start bullshit. If I rev it over 2000, it will still do it, just not as severe.

5. High RPM misfire

- Under load, the shift buzzer will go off at ~5500 RPM, and at 5800, a slight misfire begins to occur. If I take it up to 6000 RPM, the misfire develops into a scary, very rapid misfire. The car is not running lean, my AFR's are showing high 10's under boost, which I never let go over 10 pounds.

6. Fuel mileage

- I m lucky to get 12 MPG even with keeping my foot out of it.




Any help is GREATLY appreciated, before I blow my brains out trying to figure all of this out.

veedubbed

ALSO - plugs and wires are new.

Icemark

what are you using to control the 2ndaries and is your timing set stock or???

veedubbed

Stock management.

Timing is dead on FSM spec. I did notice something when I had the timing gun on the car the other day, whenever the car sputtered and whatever, there were gaps in the light, so it wasn't sparking. I wonder if I could being having a coil issue also.

ziplock

lol I have a screwy motor in my 7. Ive considered this v8 swap but Im a youngin livin the grind... plus its winter ...

As for your screw on top of the intake, mine was completely out of wack when I got mine, there is a procedure to set that properly in the FSM that I followed and that straightened things right out. Basically involves a jumper wire and some calibration.

As for the cold starting and 1500 idle, my car does this as well, I drive an auto and I just pop it into D then back into park and that fixes it up. Maybe try clutching in or something to toggle the fast idle.

ibrakestuff

well i would check the coil pack (u mentiond that is might be screwy) im trying to think but cant ,too much beer. what is it that tells your coils to fire??? that might be it or the coils. definatly check the afm that can cause alot of weird ****.

veedubbed

No, that's not the screw. This screw is in the AFM itself, and the only thing the FSM says on it is "Don't touch it." It does not however, say how to get it back in spec if someone else has touched it. I will get a new, untampered with AFM if I absolutely have to - but I would think that someone knows how to set it like it is at the factory.



I am going to try re-grounding my coils this week sometime when I get time, I will see what that does.

texFCturboII

iTrader: (17)

get a used AFM of of here for cheap.... done.

Icemark

well running 700cc injectors with no controller (even on the 2ndaries) is just asking for fuel and run issues and that is where I would start first in my trouble shooting.

I'd also be looking at the CAS, pull it and see if you get even pulses when you spin it at a consistent speed.

What condition were the spark plugs when you removed them? Black? Sooty? Burned white?

Also LT1 RX7 comments have been removed from this thread. The thread originator was asking for help fixing his problems, not is swapping motors.

veedubbed

Secondaries should not effect my idle at all though, should they? And what makes my car die (more or less) when the initial set it jumped?

texFCturboII

iTrader: (17)

I don't understand what you mean by saying "jump the initial set"

veedubbed

The initial set connector that kills the BAC in order to set the idle with no correction.

texFCturboII

iTrader: (17)

I'm having issues with that too as of late. But I'm dealing with a bad TPS..... yours seems to be in spec, intermittent failure maybe?

veedubbed

Opened up my throttle plates a little with the set screw and that cured my initial set problem.... BAC couldn't provide enough air with the plates all the way closed.

I'm going to buy another untampered with AFM next, so I can eliminate that screw as a problem. I am also going to look into getting an SAFC for my fuel, as well as two cleaned 550's. I forgot to add that I do have a Walbro 225 in the tank, wired for 12v all the time, so I am for sure running rich at idle.

Icemark

probably just short of flooding... Probably costing yourself about 50 HP too, running that rich all the time. No wonder you get such shitty mileage.

Don't you read anything on tuning rotary motors??? Cause you did the opposite of what most rotary set ups should do. The last thing you need to add is more fuel.

Again how did the spark plugs look when you pulled the old ones out?

veedubbed

They're black.

Yeah, it makes sense now. I had thought about it before, just never really thought about it.

So how's this look?

SAFC
Cleaned 550's
Untampered with AFM
Known-good BAC


If I were to invest in those items, I think I can eliminate anything that I think might be causing the problems now, as well as lean the car out.

I noticed something tonight, that much over 4000 RPMs under boost, and my AFR reads low low 10's and then pegs at 10. Could this be causing my high RPM misfire? Just running it so rich to where the plugs can't fire?

I'm assuming now that running rich is causing all of my problems.


You say I went backwards - I did this because I lean-popped my last motor when I added the 3" exhaust and got on without watching the boost, wasn't trying to go that route again.