84 2.5 auto

Fuel pump primes 2 seconds
Have fuel at the TB (Had to pull the tank and replace the line in the tank grrr)
Injector does not open while cranking
Injector opens when you ground it out - has 12v on the pink wire
Have spark

Will start if I pour fuel down the intake - Dies as soon as this is used up

Both orange wires on the ECM have 12v
Ground on the ecm appears to be good
Blue wire on the injector ohms out fine to the ecm

SES light will not come one
Will not flash codes - light won't come on
I do not get 12v on the ecm connector for the ses light when in the key is on or run - Put my meter between this wire and a power source I get 12v - So it seems like this wire is grounded....

ECM wiring connector looks like it has been hot in the past - one wire looks rough but ohms ok - connector has some black marks on it
Opened the ecm and all the traces look fine nothing blown entirely apart
All fuses are good
12v fusable link by the battery has power - Do I need to check power on both sides of the links? Part of this wire is bare and looks like it has touched the ground strap a few times in the past - Really starting to look like something is fried somewhere.
Connector by the distributor is good

I do not have a map or tps (basket case) but it should start without these. I have a rough idea of houw a map would be connected - no idea where a tps would go.

I'm leaning towards a bad ecm - Just wanted thoughts

I've wanted to do a fiero for quite a wihle. Now that I have a notch I was hoping to at least get it running and drive it for a while, I have decided that I would rather have a gt to do a motor swap on, but was hoping I could sell this one as a running car.

Thanks for any ideas

wecome to the forum you are very specific as to what you have done heres what i would try, can you get your hands on a fuel pressure tester?
can you spray some injector cleaner on it (the injector)

quote Originally posted by Bremertonfiero: wecome to the forum you are very specific as to what you have done heres what i would try, can you get your hands on a fuel pressure tester? can you spray some injector cleaner on it (the injector)

Thanks for the quick reply - I did clean the injector as best I could, it didn't look bad to start with.
If I pressurize the lines (just using a jumper to the fp connector) and tap the ground side of the injector I do get fuel through it.
So I don't know my exact pressure, but I should be getting some fuel through it either way.

The 84 Fieros were wired a little different for the power to run the injector there is a single red wire from the alternator area that runs under the throttle body and disappears into the harness through a single wire plug similar to the O2 sensor one. This is power to the PCM and the inector and does not show up on any of the wiring diagrams I have seen. Dan

quote Originally posted by FIEROFLYER: The 84 Fieros were wired a little different for the power to run the injector there is a single red wire from the alternator area that runs under the throttle body and disappears into the harness through a single wire plug similar to the O2 sensor one. This is power to the PCM and the inector and does not show up on any of the wiring diagrams I have seen. Dan

I have power at the injector though...

Hey,Gabbi

I would lean towards the ECM as well. Without the SES(CHECK ENGINE in the '84) sounds like a faulty brain to me.

I have a ton of ECM's laying around,just get me the #'s off of it,and I'll see if I have one. You are welcome to have it.

On my experience with the '84's,when the fuseable link goes,you lose power to everything.Totally dead.

So,if you have juice all over,my guess is that you are good there.

Take care. Good luck!

-Mark

Thanks Mark! Pricing on ebay seems to be a bit high since they are getting rare.

When I get home tonight I am going to cut out the fusable links just to make certain.

I'll get back with you.

#16 on the white ECM connector should be 12 volts from the IGN switch. This also feeds RED (or pink if its faded) the current to the injector. Check for 12 volts at the ECM. If no voltage, there is the open circuit.

The ECM opens the injector by grounding the return side BLU of the voltage to the injector. If this ground wire between the injector and the ECM is not open, bad ECM.

[This message has been edited by 30+mpg (edited 01-19-2009).]

Connect a test light between the terminals in the injector connector and crank the engine, the light should blink. If not, and the integrity of the wiring is verified from the injector harness to the ECM and to ground then suspect a bad ECM. No check engine light tends to confirm this, but verify the CEL bulb and connections are good. The ECM will not fire the injector if it does not see EST pulses from the module, check the tan wire from the distributor to the ECM. The module will provide spark while cranking as it has its own built-in basic timing function. The engine very likely won't start without MAP and TPS since those are two of the three main inputs along with RPM via the module; without at least two main inputs the ECM has no idea where to start, and it's unlikely the programmers back then would have contemplated multiple primary input sensor failures occurring simultaneously.

JazzMan

With no SES light sounds like the ECM to me. Check the grounds to the ecm too, they bolt to the tranny bolts.

------------------
"DRIVE IT LIKE A FIERO"
'84 Fiero, engine to be determined
'87Blue GT 3.4L Swap Completed!!!!!!!! Boosted!!!!!!!
Las Vegas Fiero Club
Fiero Road Club Of Northern Nevada

IT RUNS!

Thanks everyone.

Now I need to start up a about me thread in general and a WTB thread for parts in the mall.

I checked so many things yesterday I got my own wires crossed.
I did ground the relay yesterday to see if it would fire - I heard it clicked but did not do this with fuel pressure.

Checked the last few things and low and behold, the ecm is pulsing the injector its just not firing.
By this point I know my ses light is just bad.

So why isn't it firing? I pressurized the system again and ground the injector a couple more times - click click - no fuel.
Hit it a couple more times and got a tiny stream of fuel out the bottom.... Hooked the harness back up and tried to crank it a few times. By now it was spraying fuel, just not in a pretty pattern.

Took the injector out of the TBI and cleaned the screen, used the air compressor and wd-40 to try to clean all the orfices. Put it back together and had a real pretty (but tiny) stream of fuel. It would fire but would not run.

Ok, now remember I have no alternator, tps, or map - So the ecm has no idea whats going on other than dissy pulses and hei sparks.
So I grabbed the map from an extra lt1 intake - Plug wouldn't fit - Rigged it so that the pins were touching - I figure this isn't what the ecm wanted, but better than nothing.
Still no tps.

Fired right up and idled for a minute or two - No belt so no water pump. It was quite rich and puffing fuel out of the pipes, but didn't not seem to have coolant or oil in the exhaust. I was going to pull it out of the garage and put the Mustang back in - but the little Duke needs the rest of its parts. Much throttle or load and it would stall - But it is running on its own now.

Is this the car that was on Craiglist last week? White....damaged front bumper cover...? I have some parts you might need.

Mirrors?

I was wondering how much of what I was told was true.

I'll send you a pm