Car will not start/RobTune ECU

[dankberries]

OK to start I have a 93 impreza with an ej23t/25d hybrid running on a RobTune ECU.

Just recently I had installed a RobTune ECU, My car had been running great without issue for about 200 miles.
As it goes, I drove the car home one night with no issue. Everything working great. Went out the next morning to start my car and I was getting NO firing of any kind.
I began basic diagnostics, checking fuel and spark. I found the fueling to not be an issue, but when testing spark I was only getting spark on 1&2 cylinders. My first thought was to swap the coil pack, which didn't fix anything. My next thought was the ignitor chip, although I've never heard of one going out. In my current setup I'm using a SVX ignitor with the 4to2 wasted spark setup. Unfortunately SVX ignitors are expensive and difficult to find, so I didn't have a back up to swap in for testing. Instead I decided to try using tandem Legacy ignitors since I had a few lying around.
After converting to tandem ignitors I was able to regain spark on all four. Unfortunately the car still doesn't start. Some weird partial firing popping is happening(sounds way off) and actually some little puffs of smoke are coming out of the intake! Wierd! Because this is happening it lead me to think I wired the ignitors 180° off or something. So I flipped how had them connected and it made no change.
For the hell of it just in case by some miraculous way my car jumped timing over night, I decided to check it, but my timing is perfect.
And just because I can try, I swapped cam and crank sensors, nothing.
Current ECU codes are 24 & 45 . I've had the car running w/ these codes so I'm not leaning toward them. I hadn't removed pin.48.5 yet so that's reason for code 45. The IAC code is a mystery ghost code I can't get rid of.
Checked voltages at the injectors, all four are reading. My injectors themselves have only 200miles and have been test flowed and cleaned.
Im kinda at a loss of what direction I should take next, perhaps someone has some insight?

[dankberries]

I should also mention it sounds for sure like it has compression, and its a freshly built engine with only 200miles on it.
Also if somebody knows, when grounding the ignitors, its OK to ground them right to chassis or should they be spliced in with pin47.15 ignition ground?
In the 4to2 wiring write up it shows in a diagram that they should be with pin47.15 but in the write up it didn't explain anything of doing that.

[dankberries]

Also, my impreza has been running successfully as a 22t swap for a couple years now.
Problems started after recent modification.
New setup, ej25d heads
RobTune engine management 7+ tune
4to2 ignition conversion

[dankberries]

I think it maybe an intake manifold backfire I'm hearing and seeing, in which case makes me think timing(way more than one tooth off), or perhaps a leak on the manifold.
I would like to believe that this many priblems don't just occur overnight, and that my problem is with the ignition given what I've found.
When I get a chance I'm going to swap out the IAC, again, and reset the ecu to see if I can clear my codes. I will also double check my timing and a pressure test.

[dankberries]

Slight update:
I swapped in another IAC, double checked timing, moved pin 48.5, and reset the ecu.
Car still does not start. Same symptoms are occurring, sounds and smells like partial off firing with smoke poofs coming out of the intake.
ECU is throwing codes 24 & 45 despite the changes.

[Legacy777]

Hmmm,

I agree about the smoke out of the intake usually indicates a timing issue, but it sounds like you've checked that.

Is there any way to eliminate the Rob tune ECU and go back to how things were setup before? That would help eliminate some of the possibilities. Igniters don't typically just die. So I'm wondering if the wiring going to the older SVX igniter might have been the issue, vs the actual igniter....and just moving the wiring around got it working partly again.

[dankberries]

It would be a serious pita too get a 22t ECU going again, I have many modifications.

I tried everything to get the SVX ignitor to work again before switching to tandem ignitors. I do believe something happened to it.

[dankberries]

I'm still not sure if it matters to have the ignitor grounds shared with the ignition Ground pin 47.15 or if its OK to ground them on the chassis.
I'm asking because my SVX ignitor stopped working and was ground straight to the chassis, not sure if theirs a correlation or not to it failing.

[MikeyMeyagi]

ground the igniters to a good chassis ground. go back over your wiring on the tandem igniters, something is wired wrong and your firing order is wrong. ive done a bunch of these and had this same issue. one of the pictures on the 4-2 conversion thread is wrong i think, there should be a note of it.

[dankberries]

When I get home later I will take a pic off my configuration. Its pins 7 & 10 that are incorrect in the diagram and I understood that.

[dankberries]

ECU pin:
47.7 to ignitor 2, pin 1
47.8 to ignitor 1, pin 2
47.9 to ignitor 1, pin 1
47.10 to ignitor 2, pin 2

Ignitor 1(top)
Ignitor 2(bottom)

Ignitor 1 out :
pin 5, 3/4 ignition
pin 6, 1/2 ignition
Ignitor 2 out:
pin 5, 3/4 ignition
pin 6, 1/2 ignition

[dankberries]

PhyrraM's diagram:

[MikeyMeyagi]

id swap your 1/2 and 3/4 wires and try it

[rob]

I think the diagram is incorrect. You should be pairing signals from ECU pins 10/8 and 9/7. The diagram shows pairing 10/9 and 8/7. To fix, just swap #8 and #9.

Here is the installation picture for my 4to2 converter if it helps.



-Rob

[dankberries]

Well I'm not haven much luck.
Here's what I've kinda figured out, if I leave my wires how had in my picture configuration, I only get spark on two cylinders. However if I flip the outputs on a single ingnitor(not to be confused with both ignitors) I can get spark on all four. I can do it to either ignitor but not both at the same time. Showing that their is only two options to gain spark on all four by changing outputs.
Now,
If I take Robs input configuration 7/9 to one ignitor and 8/10 to the other ignitor, and leave the outputs how they are in my picture, I only get spark on two cylinders, however if I switch the outputs on a single ignitor I can get spark on all four.

Car still doesn't start. When all four spark I can hear and see the intake backfire, despite flipping the outputs.

[dankberries]

Update** noticing possible problems with my timing belt tensioner, decided to check timing a third time and I noticed the belt seemed too loose, going to take it out and see what's up..

OK, this is crazy, on this last timing check I found the crank to be 180° off and my belt seems very loose, I'm totally confused how this has happened. I was using an older style tensioner(brand new) but I'm going to pick up a newer style tensioner and see if it helps. More updates soon..

[rob]

Well I'm not haven much luck.
Here's what I've kinda figured out, if I leave my wires how had in my picture configuration, I only get spark on two cylinders. However if I flip the outputs on a single ingnitor(not to be confused with both ignitors) I can get spark on all four. I can do it to either ignitor but not both at the same time. Showing that their is only two options to gain spark on all four by changing outputs.
Now,
If I take Robs input configuration 7/9 to one ignitor and 8/10 to the other ignitor, and leave the outputs how they are in my picture, I only get spark on two cylinders, however if I switch the outputs on a single ignitor I can get spark on all four.

Car still doesn't start. When all four spark I can hear and see the intake backfire, despite flipping the outputs.

I think you misunderstood what I was saying. The outputs of the two igniters need to combine signals from 10/8 and 7/9. That does not mean, route 10 and 8 to the same igniter.

From the original diagram, swap the inputs to igniter #1 ( bottom of the diagram, top in your picture); so from ECU-9 to igniter#1 pin-2 and ECU-8 to igniter#1 pin-1.

Or, to show the change compared to your previous listing;

ECU pin:
47.7 to ignitor 2, pin 1
47.8 to ignitor 1, pin 1
47.9 to ignitor 1, pin 2
47.10 to ignitor 2, pin 2

Ignitor 1(top)
Ignitor 2(bottom)

Ignitor 1 out :
pin 5, 3/4 ignition
pin 6, 1/2 ignition
Ignitor 2 out:
pin 5, 3/4 ignition
pin 6, 1/2 ignition

From this you should see 4 spark events. If it still spits back then swap the outputs.

You have to get the input pairing right first, then you need to get the output matching the coil banks.

I am also going to guess you have fouled your plugs by now, so might as well pick up an extra set.

[dankberries]

Update:
Car is running again!
How this all happened so abruptly I have no idea.
Some how my crank timing came off substantially and my ignitor failed.
I put in a new style tensioner and seems to hold a little tighter. Not sure if anyone doing dual cam swaps has had issues with older style tensioners but I think its better to just upgrade to the new one, although their pricey at 150$.

[rob]

Good news. Can you confirm your final igniter wiring?

-Rob

[dankberries]

Ugh..FML...
Just put another 60 miles on the car, everything running great, pull up to the liquor store, turn the car off, run in, come out, go to start the car, and its having a hell of a time, finally it starts, but sounds like shit! Like my timing/ignition has gone wack again!
Smh..nothing like a little Murphy's law.
I'm going to have get a tow back home and start this process all over again. If I do in fact find my timing or ignition is out again, I really don't know how or why its happening or of a solution to fix it at this time..

Morning Update: after diagnosing I've found the ignition is still working but my crank timing has come off again! I'm having some sort of issue with jumping timing..
I did some research and noticed on usdm WRX's they have an extra little pulley on the tensioner bracket, maybe I need to convert to something like that? Why would I be jumping timing?
Seems like it occurs when starting the car..

[mike-tracy]

I would be suspicious of the tensioner you have in there. I would also be worried about your valves since you have an interference engine.

One thing I do after putting the timing belt on and tightening up all the pulleys & etc. Is rotate the crank forward about half a revolution, then counter-clockwise half a turn, then forward again several full revolutions till I see that the timing marks line up. A mechanic told me about rotating the crank backwards for half a turn or so - said that the back and forth movement makes the tensioner "tensioned" properly from the get go.

[dankberries]

Here's the two tensioners I've tried, both brand new:

[dankberries]

USDM wrx tensioner has extra pulley:

[MikeyMeyagi]

ive run both styles on 22t/25d hybrids with no issues ever on jumping timing.

[dankberries]

Good news. Can you confirm your final igniter wiring?

-Rob

Correct order -

Top Ignitor :
Pin 1 - ECU pin F47.9
Pin 2 - ECU pin F47.8
Pin 3 - Ground
Pin 5 - Out signal 1/2
Pin 6 - Out signal 3/4

Bottom Ignitor :
Pin 1 - ECU pin F47.7
Pin 2 - ECU pin F47.10
Pin 3 - Ground
Pin 5 - Out signal 1/2
Pin 6 - Out signal 3/4