RX200013B

what i have
86 s4, emissions removed,fuel pump hard wired,stock everything else

my engine will start and idle(little ruff)untill warm. try to start again and just spins,
disconnect the fuel pump and it tries to fire, connect fuel pump again and start, i get one little puff and then just spins.

would this be bad injectors?

EnjoiPugs

Have you tried the standard unflooding procedures. I am not saying that's what it is, but it might be leaky injectors, hopefully someone who is more knowledgable than I will respond in aid to this. This is directly from the FAQ:
My car doesn't start
Remember when starting a fuel injected car you should never pump or press the accelerator pedal, but if it won't start it is probably flooded, Hold the accelerator pedal all the way down while cranking, do not pump the pedal. If it still doesn't start after a few tries, Then remove the EGI fuse and crank a couple more times, then re-install the fuse and try starting again. If then the car still fails to start it then you need to remove and clean the spark plugs, put in a teaspoon of good quality 20W50 motor oil or a teaspoon of ATF into the lower sparkplug holes, re-install the spark plugs and try again. Make sure you change your oil after you have started and run the car ASAP.

RX200013B

YEP, thats what it does , unplug the fuel pump and crank. it will try to start and then runs out of fuel. connect fuel pump get one little puff and then just cranks and cranks.

lookig for a conformation that i have BAD injectors

calpatriot

Your symptoms are consistent with a flooded condition. This may be due to dirty injectors (when was the last time these were professionally cleaned? Should be done every 30k miles as a preventative maintenance item); low compression; or other problems.

What do you mean by 'fuel pump hard wired?'

You can verify the flooding problem (common in the S4) by wiring in a switch to cut off power either to the injectors or the fuel pump. Crank it with full throttle and the fuel cut off until it jumps, and then release the switch while still cranking, and it should fire right up.

That's a workaround, not a fix.

If that turns out to be the case, check the compression. If it is good, have the injectors cleaned.

Are there any trouble codes on the car?

RX200013B

hard wired means that the fuel pump is constat on with key switch

no trouble codes as this is a swap into a b2000

compression is good as it starts everytime cold and idle for a little but it is really ruff, like it is getting to much or not enough fuel and dies after warm

ifryrice

It sounds like just about every other hot-start out there. It's almost always made worse by low compression. Dirty injectors, faulty water thermosensor/air sensor, and a lack of a BAC valve are all contributing factors. Generally start with a compression test to see where you stand, then clean injectors (if it's to the point that you can't get it running when hot), while you're there reseal/recap/double check all your remaining vacuum lines.

calpatriot

OK, so this engine is in a B2000... did you put in the stock RX7 ECU as well, or are you controlling the ignition and injection systems some other way?

HAILERS

About STARTING.

When you go to start, does the ECU see the start signal? Did you rig it so the ECU will see the Start signal. Start signal being the voltage to the trigger wire on the starter solenoid.

Normal RX have that trigger wire spliced to a wire that goes to the ECU so that the ECU will know the engine is being started. When it sees that signal, then the ECU uses an internal start fuel map for fuel injection ...until the rpms reach over 500 rpm whereupon it now uses the AFM signal for fuel.

Hot starts are actually helped by the ECU NOT seeing that start signal. IF the ECU sees no start signal while you start, then the ECU uses the afm for fuel delivery. Much less fuel used that way during starting.

A cold engine is hampered during start, if the ECU does NOT see that signal.

Helps to make sure the water thermo sensor is also being seen by the ECU. IF the wire is open b/t the ECU and water thermo sensor, then the ECU defaults to a 176* engine temp and delivers not enough fuel if the engine is cold.

3B is the wire that is a input from the starter circuit when the key is HELD to start....on a normal series four ECU/CAR.

RX200013B

YES, using stock ecu n326

[QUOTE=HAILERS;9515842]About STARTING.

When you go to start, does the ECU see the start signal? Did you rig it so the ECU will see the Start signal. Start signal being the voltage to the trigger wire on the starter solenoid.
[END QUOTE]
yes, the starter wire is connected to the ecu

well, i had another set of injectors and sent them off today, hopefully be back on friday and see what happens

thanks for all the help,

RX200013B

calpatriot

If you have a stock ECU, you can access trouble codes on the two wires that normally would have gone to the test connector. Those codes, if present, might point you in the right direction.

HAILERS

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That's something I had not thought of. You could buy two buck fifty LED from Radio Shack and put the negative side of one LED into pin 1A and the neg side of the other LED into 1B. The positve side of the two LEDS to any source of power like pin 3I or 3J on the far left of the small plug on the ECU. All connectors left connected to the ECU and LED's backprobed into the wires mentioned.

See attached jpg as to how that worlks.