Recap: Its a 1972 dart with 440 and electronic ignition, a while back it refused to start, it would try and hit but just wouldnt start. I swapped out the ECU box and it fired right up. well, its doing the same exact thing now so i have now put 2 ECU boxes on it and its still doing the same thing, just hits but wont start, but surely both new ECU boxes arent bad, is there anything else that would have the same symptoms as the ECU bad? Would the voltage regulator cause the same thing? I got to get it back running.
thanks

Does your ECU have a ground wire coming off where it mounts to? Heard not having a ground can cause ECUs to go bad. Tried a new Ballast resistor?

you might check your reluctor gap and or plug in an extra dist & spin it by hand & see if it gives you a good spark.

I bypassed the ballast to see if that was it, no go.. I dont have another distributor to try.. I swear though, it acts just like it did when the first ecu went bad..

what does the gap need to be between the reluctor and pickup?

Yeah I had a couple of ECU's go bad just from sitting, threw me for awhile especially by the 3rd time I wasn't even thinking ECU.

.008 but you might reduce it to .006 but make that at the closest part as the reluctor/magnet usually aren't parallel & note your shaft side play while you're at it.

I went to oreilly and got another ecu, same thing so i figured it was faulty, so i took it back and went to autozone and bought one and still the same, so i dont think its the ecu this time even though it acts like it did when it went bad the first time..i dont know, im going to check that gap but i dont think thats it, any other places to look?

You might take the dist that's in it out & spin it & see what you get for spark & check the other (2)basics fuel & compression. Plugs look OK? It just started acting up out of the clear blue w nothing being changed.

Have you tried a new set of plugs? You might have gas soaked the ones in there now.

Change the plugs. A friend went through this same thing on his 67 Cougar. It turned out that the weak Optima battery would crank it just enough to spin it decent, but not fire the fouled plugs. Drop a new set in and it fired right up.

plugs are fine, what i dont understand is that its acting EXACTLY the same as it did a month ago when changing the ecu fixed it, its doing the same thing being that when cranking it over it acts like it wants to start but wont, if i put a jumper battery on it and get it turning over real fast it tries to run but just wont, just like the time when i replaced the ecu and it fixed it, now the ecu's arent fixing it..

could you have some one crank w the key while you hold the coil wire 1/4" from ground & see if there's continuous sparks

Block to body ground.

You need to check for spark and fuel.
Pull a plug wire and see if you have good spark.
I bumped the coil wire on my brothers Dart this past summer putting the air cleaner back on after adjusting the carb. for a stalling/not wanting to start condition and the engine wouldn't restart. I pulled the coil wire out of the coil and it was so burnt up I don't know how it ever ran.
I put a used coil wire on it that I had laying around and the car fired right up and purred like a kitten.

Is the ECU a 5 pin? I wents thru this a little while back on a car, it was wired with the MP kit and 4 pin ecu, when the ECU took a dump I got another from autozone and didn't notice it was a 5 pin- I thought they have been obselete for years.

On mine it would crank and sputter but not much else, after I figured out the problem I ran a wire from the ballast to the 5th pin and it hit on the first crank.

The voltage regulator wouldn't have anything to do with it, it's not part of the ignition.

I would look at the ballast resistor also, if you have the wrong ballast it may be frying the ECU.

no, its a 4 pin and simgle ballast, although it used to run on either the 5 or 4 pin ecu, but i always use the 4-pin..

well, i took the distributor out of the block and spun it and it is making spark, i even tried the other 2 ecu's that are supposedly bad and they made the same spark, It is a bluish purple spark, i just pulled a plug wire off and stuck another plug in it while i spun the distributor, i also pulled the coil wire out of the coil a little bit and spun the distributor and it made bunches of spark. with the ballast plugged up im only getting 5.5 volts to the coil and with the ballast bypassed im getting 8.5 volts to the coil..still wont run after all this messing, i did ohm the pickup coil and its 276 and it changes if i spin the distributor shaft but ends up back at 276, saw on the tech archives that it should be between 375-425, but i thought these either worked or didnt work at all, meaning no spark produced? what the heck do i do now?

Have you tried using fresh gasoline.I like to have worn one of my legs out once trying to start a motorcycle.Come to find out,the gas would not even light with a match.

We got good spark. & those voltage readings were during cranking? I would still keep it simple & check compression EDIT your ECU's/dist pickup are good. If your initial is good is it possible that the chain has jumped? Please do a compression test.