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AS posted on USMB: i know some of you are the best and brightest and could use all the insight I can get

Ok all,

here is the situation. As some of you know, I am putting a 99 2.5 SOHC (MAF Based) in my 97 impreza body. I have the new engine in, the right ecu and the wiring is spliced in. Fuel is getting to the engine and the air intake seems to be fine, but we are having trouble with spark.

I get weak spark across one coil and none across the other. There are four wires going to the coil/ignitor one for ground (reads at like 2ohms so its grounded), one for ignition switch power (reads at 12V) when the car is on run, then there are 2 signals, there is continuity from the ECU to the coil over the wire. When the engine is kicked over, one of them gets an alternating voltage (like it should) and the other gets NO voltage.

My only guess is there is something else that controls the signal coming from the ecu to spark...what is that??

Oh yeah i have ruled out the coil pack itself as i had a car there with one and mine worked fine in it and the good one from the other car exhibited the same problem when in mine.

Lets just say this all makes and engine that doesnt work, We are wondering if the timing being off would retard anything or keep it from sparking as a safety feature or something??

Any help would be a Godsend....im desparate

The above emoticons show the emotional roller coaster of an engine swap

Cory

PS i had a little engine ground wire that was cooking to death from over current. The engine ground is hooked up and secure but i still had to add another strap to keep it from cooking...dont know if this helps but i thought i would include all relevant info

I don't see any emoticons.

I'm not that familiar with cars and engines as new as yours, but I wonder if there's any chance this has to do with integrated vs. separate ignitors.

Your stock engine had a 3-wire coil pack mounted on the intake manifold, right? With the ignitor mounted on a pedestal in the middle of the firewall?

You're not using the stock ignitor at all anymore, right?

no the stock ignitor from the 97 is wired to nothing its taken out of the loop

Hm, well, if you have the pinouts of the new coil pack and of the new ECU correct, then I wonder if the ECU might be faulty. You're getting spark from one channel (what makes you say it's weak though?) so it's doing something right.

Maybe also check that your cam belt is on right though. If valve timing were off the right way you could end up with this weird situation where one channel sparks at the wrong time and the other doesn't spark at all.

And what's this ground strap that was cooking? Where was it attached and how thick was it?