Ottoman

i've got a Euro Spec FC...

i bought it with this problem.. and the car sat for a long time due to more pressing matters..

well now that my FD popped a seal, and my TII FC is on the bench getting ready for a rebuild..

this car is my only car so ur help and input is greatly appreciated..


the euro spec is diff a little then the US spec.. i still have a stupid Dizzy.. and no MAP sensor on teh passenger shock tower..

basically..

car starts fine, idles fine.. revs fine... EXCEPT under load

it "felt" to me like a secondary injector problem...

if i go easy on teh peddle (low TPS%) I can rev it out to redline no problem...

if i go WOT and mash the pedal while parked, the car will reach about 5k and then Peg there... as if i'm bouncing off an invisible rev limiter...

same thing under hard driving, car will reach 4-5k and just fall on it's face...
if i slowly roll up to high rpm it's ok.. as soon as i gun it falls on it's face..splat..



i've changed the fuel filter, changed the fuel pump, had the injectors cleaned.. so i know it's not a fuel problem...


only mods on teh car is RB headers, Apexi N1 and a cone filter...


i dunno if it's an ignition problem, or a screwy sensor...


i've searched for similar hesitation threads but many talk about the map sensor which i don't have, some ppl said fuel filter.. i changed all that it's not fuel..

i changed spark plugs... 9's all around....


I have a video of the tach if anyone wants to see it.... to better understand...

i'm lookin for idea's as what would cause it to peg like that



the only thing the previous owner told me.. which i'm not so sure..

is that the car was running fine, he took it to a local place (who are not rotary knowledgable) to have his RB headers installed..

rather then installing the headers from below.. they removed the intake manifold to acess it from above..

when it was all put back together.. apparently this problem started...

but when i took off the UIM i didn't say anything odd...



anyone have ideas?

Ottoman

i've been doin some experimenting... i have a hunch that it maybe the air flow meter...


would my T2 flap work instead of the N/A Flap AFM?

GXLBidwell

did you check for leaks in the intake?

Ottoman

i've discovered something new.. and why I think it's the AFM (unless it is an intake leak)


when the engine is dead cold.. i can crank till the battery is dead it wont start.. (spark plugs are barely moist)


if i get a partner to "push in" the door of the AFM the will fire right up...

after that it'll Idle ok around 1,000 rpm... and has the ocassional burp/popping but that's not unusual considering i have no cats...


so is it the AFM u think? ( i dont have a Dig. volt. to check resistance, only a crappy analog one)

WonkoTheSane

iTrader: (2)

Your analog one should still do the trick if you know how to read it.. If not, drop the 15 bucks at a local dept.. store for an "el cheapo" model digital one. Your AFM controls a lot, especially related to fuel. I would do a thorough check out.. I can't answer whether they are the same for a TII or not, the FSM would note any differences, though.

iceblue

You have both a TII FC and a NA FC if I gather right? All S4 I gather. Is this right? Ok if the injecors are the same IMP try this it will work perfectly.

Swap your TII afm into the car and swap the TII 550cc injectors into the secondary spot. Evrything will work now.

Ottoman

hmm the notch on the N/A injectors is diff then the notch on the TII injectors.... (one is center one is offset) my TII has high Imp... N/A low



something else i noticed... with the car not running, and just "push in" the door of the AFM.. i can hear the fuel pump click on.... and start pushing.. dunno if that's "normal"


keep it coming guys...

I need everything i can get!

RETed

Ok, we need to isolate it to either fuel or spark to make diagnosis easier.
Since you can replicate the problem pretty easily, try this...

Pull the spark plug and clean them up as best you can.
Get a brush and take off as much crud as you can.
Keep a mental note of how they look when you cleaned them.
Put them back in the engine...rev the crap out of the engine at idle (5k?) a few times, and immediately kill the engine.

As soon as the spark plugs are cool enough to handle, pull them.

How do they look?
If they are WHITE and CLEAN, it's losing fuel.
If they are BLACK and WET WITH FUEL, it's an ignition misfire.


-Ted

Ottoman

thanks Ted, i'll try that when i get home


what do u think of the AFM issue? (wont start when the motor is cold unless i push the flap door then it fires right up)

think it's related?

MARTIN

check your thermosensor...

RETed

I've only ran into that problem ONCE, and it was because the S-AFC was programmed wrong. :P

I don't suppose it has some kinda fuel controller in it?


-Ted

Ottoman

is that the IAT? on the other side of the many above the rat's nest?


nope, not yet.. i was thinking of wiring my S-AFC II to it, just to get the sensor/voltage checks and see what the AFM % is reading at idle and at WOT when it pegs

cone filter, RB headers, N1 catback, otherwise bone stock 91 model Euro FC with a Dizzy...



speaking of what is that pip that splits off the bottom and goes up around the back of the intake manifold to the other side near the rats nest? part rubber part metal

HAILERS

Car only starts when you push the AFM door a touch aft? It's possible the circuitry to the Circuit Opening Relay is not quite right.

To prove this is the case, there is a yellow, two socket connector near the right strut tower/boost sensor area. Jumper the two sockets with a piece of wire. Then try to start the car without pushing the afm door aft.

The amount of fuel programmed for STARTING bypasses the afm. It's a set amount dependent on the cranking speed being below approx 550 and the water thermo sensor. So the car should start even without the afm connected (electrical plug). Only for a moment though, but should start up.

So, what I'm suggesting is, that the fuel pump is not working during START. It should run when the key is HELD to Start. There are two coils in the Circuit Opening Relay that have the potential for pulling in the Circuit Opening Relay and making the fuel pump run. One coil is pulled in by the Starter circuit. The other by the afm being moved aft and making a set of contacts inside the afm. A way around this AFM circuit is to jumper the yellow plug I described. If the car now starts, then I'd suspect the switch inside the afm is not set right.

EDIT: I re-read your post about how it won't start when dead cold. Two ideas one which was mentioned already. If the water thermo sensor is disconnected or bad???? then the ECU defaults to 176*F. So it is a Known, that during the START CYCLE, the ECU looks at cranking speed being under 500rpm and the water thermosensor temperature. If the temperature is cold, like in the 40*F range, the opening duration of the injectors will be set at something like 45ms. But if the ECU is seeing a temp of approx 176*, then the opening duration will be on the order of 17ms. Quite a difference, eh??? Yes.

So, put a meter on your ECU pin for the water temp sensor and see what it reads with the engine running. A fully warm car will see approx 0.45 to 0.50 vdc.

If the meter is on this pin while the car is warming up, the voltage will go from the 2plus vdc range and slowly fall down to the 0.45-0.50 vdc range when the car gets fully warmed up.

Another thing to look at on the ECU is for the START signal. On my USA series 4 that pin is 3B. IF the ECU doesn not see this momentary Start signal, then it will NOT inject enough fuel during START. I've been there and seen that. Even a warmed up engine will get the injectors to stay open approx 17ms in the START mode, but if the input to pin 3B is missing, the injectors will only open 2-3 ms.

The Start signal is approx 12vdc as long as the key is held to Start. Actually somewhere b/t 9-12vdc due to the voltage drop from the starter being spun over.

Your problem could be a lot of things. I just gave you a couple more. Go here http://wombat.sevarg.net/RX7/RX-7_Training_Manuals/ and just download the Emissions and Fuel chapter. It's only about forty pages or so. Look towards the last few pages and find the chart for the Starting cycle or Cranking cycle.

Ottoman

nope when the car warm it's ok (residue fuel in the chamber perhaps?) usually fires up on the 2nd crank

but in cold mode it just cranks like it has no fuel.. rarely "catching"


when i push the door with the Key ON but the engine off, i can hear a relay click some where (dunno if that's normal) and pretty sure the pump starts running

I connected a Fuel pressure gauge after the fuel filter.. when cranking the FP is around ~40 psi... when u stop cranking it goes back to zero.. with the connector jumped it stays at that pressure...



but i still have the hesitation problem regarldess of engine temp...

HAILERS

I edited my first post. Please read the part where I wrote EDIT:

Since the fuel pump is a pumpin, I without a doubt, would take a look at the START signal at the ECU and also look at the water thermo sensor signal from the ECU.

On a USA car, the start signal is appox 12vdc at pin 3B. The Water thermo sensor signal is at pin 2I on a USA car.

The water thermo sensor signal...........if the key is OFF, and you backprobe the pin 2I you should see something like 2 or 3K ohms if the car is cold. IF the car is fully warmed up and the key is off, the ohms will read in the 300 to 350 ohm range depending on how long ago the engine was turned off.

It'd be better to backprobe 2I with the engine cold, meter on vdc, and then start the engine. The voltage should slowly drop down to approx 0.5vdc once the engine is up to full temperature.

By the way, I have deliberatly pulled the wire from pin 3B (start signal) and on a cold 40*F day the sucker will not start worth a darn because the injectors are only staying open approx 2-3ms vs what they should be staying open which is in the 45ms range. If I reinsert the pin in 3B, the car starts just dandy.

It sounds to me like a water thermo sensor or the voltage missing from 3B. I know zip about the Euro ECU pinouts.

Ottoman

my S4 TII engine is in pieces at the moment anyway.. and didn't have any cold start problems..

perhaps i can just try swapping it onto my N/A car... and see if that helps..

it's the one on the back of the water filler neck right green in color?

HAILERS

yes. Personaly I'm a bigger believer in a open circuit than a bad water thermo sensor. Something like one of the sockets in the sensors plug being pushed back not making contact. That sort of thing.

Looking at the output of the waterthermo sensor while the car is running makes mor sense, to me, than just changing out parts.

Ottoman

i'll try that thanks hailers.. it's just that i don't have a good voltimeter at the moment... (they're pretty pricey locally)

Ottoman

my AFM code is N323 13 210

is that the same as the US spec counter part?


do u guys have this ECU in the states?

here's what i'm dealing with incase anyone is curious:

RETed

Hey, is the ECU normally bolted down or is it just dangling there???

It might help to bolt the ECU down?


-Ted

Ottoman

yea it's bolted down... i just took it off for the pic to get the code...

what is the box next to the ecu for? my S4 TII doesn't have it

RETed

I think that box is either auto trans, power steering, or ABS?


-Ted

boosted1205

iTrader: (9)

Your AFM angled that way will cause weird hesitation problems. It must be ribbed side up or down and level since it's a flapper door .

Ottoman

thanks bud..

yea i did that... made it pefectly level, and horizontal...

didn't make a damn...


i think i'm gonna start browsing for a used AFM soon... after i try the temp sensor.. (made its stuck in "Cold start" mode and not letting it run?

i had a strange problem on my TII that went away when i unplugged the IAT sensor

iceblue

That is a ABS computer Ted.

I just want to know how you got ABS on a NA with a dizy cap.