No spark "STILL NEED HELP"

[RJfestiva]

What year is your Festiva?

[Tom]

You could unhook the fuel line lead after the fuel filter towards the engine and turn it over and see if your getting gas.

[Gforcefd]

Does anyone know which wire is the power wire for the ecu, whats its color or pin position?

[Gforcefd]

Okay I have found the constent power wire (white/red) for the computer, I know that has power, and there seems to be a few grounded sources so im sure the computer is grounded. We have power to the coil pack but its not actually sending a spark. I replaced the distributor, the Ignition module, and coil pack are all from a working car. But still no spark to the distributor. The computer ECM seems to be fine. Im totally out of ideas. Im still not totally understanding the IGN signal thing. Does it send a signal from the Ignition modul to the distributor, then back to the module saying "okay send a spark"? Im totally lost. If anyone wants to call me Im working on it right now, my cell is 607-379-1140. Im going to erase this number tonight, so anyone that gets this and thinks they have a idea call me.

[RJfestiva]

...We know the coil is good, that little black box behind the coil that I believe is the ignition module according to the service manual is good, I check it with another known good one...

Yes thats is the ICM, the device inside the dizzy is the Crankshaft Position Sensor (CKP) which takes the place of the pickup coil in older models.
Thats why I asked what year model you have.

Assuming the crank is turning the cam, the cam is turning the distributor, the CKP is producing a signal because you now have a known working distributor, coil and ICM, then all that's left is what provides the signal to the ICM. e.g. the PCM, or if you don't belive the PCM is bad, or have already swap it then wiring is the next thing to check.

[Gforcefd]

We already swaped out the pcm with another known good one, and checked the continuty of the wires going from the coilpack to the pcm, and the wires going from the distributor to the pcm. The two wires on the distributor yellow/black, and yellow/blue both have good continuity. THe only thing I question is that there are two different yellow/blue wires (1 on each plug) going into the pcm? Are both of these these wires coming from the distro, because one of them doesn't have continuity from the distro to the pcm.

Im getting ready to have to say good bye to this festiva, its so sad.

[Gforcefd]

Okay I was thinking on it abit, considering I have changed everything possible now, including the ignition switch, that could have to do with the spark, but what if the car is not priming the fuel pump to start(dead fuel pump im thinking). If the computer doesn't see any pressure, would it still send a spark out of the coilpack? Its the only thing I can think of to get the car running.

I am going to probably get rid of it after christmas cheap, but I just can't believe I can't fix this.

[packrat427]

When my pump went , I still had spark .

When someone cranks it , can you lay your ear down on the floor in the back and hear the pump trying to run ?

[FestYboy]

the fuel pressure doesn't affect the spark output, you'll get spark (assuning everything is working properly) weather or not you have pressure. you should be able to hear the pump priming with the key on and engine OFF, every time you put the key in the on position, the pump should prime.

[Gforcefd]

In none of my festiva's can I hear the pump prime, thats just why I am wondering about it.

[packrat427]

the fuel pressure doesn't affect the spark output, you'll get spark (assuning everything is working properly) weather or not you have pressure. you should be able to hear the pump priming with the key on and engine OFF, every time you put the key in the on position, the pump should prime.

NO , you will not hear it prime with the key on and engine off , the pump will only run while cranking it .

[FestYboy]

well mind you i have a carbed festy, but in all the FI cars i've been in, the pump primes with key on engine off. never came across a car that needs to see crank signal to arm the pump circuit.... wierd.

anywho, there should be a schrader valve somewhere on the fuel rail, you should be able to see if you have pressure there or at least fuel flow after cranking the engine a few times. if that fails, look to make sure you have power to the pump when cranking, all you need is to disconnect the plug under the access door and look at a volt meter when cranking, should read batt voltage (at least 10.5V). if there's no power, trace the wires to either the relay, or the fuse (or both) and test again. somehow i doubt that mazda interlaced the fuel pump relay into the ECM, but i could be wrong.

[Damkid]

the only thing i can suggest is try changing the computer, even if you beleive it's still good, change it just to be 100% sure

[hopy-d]

Have you checked the continuity of all the ground wires? I had a 90 festiva that was in the same condition as yours and I was about to give up when I found the distributor ground wire (in the loom above the fan shroud) was broke. I also know of two others that had the same condition and their problem ended up being bad grounds under the dash. Good Luck!


God is good
Hopy-d

[neanderpaul]

At least you are learning as you go. I'm a bright side kind of guy. Good luck.