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phantom no-start...low fuel delivery?

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Fresh 11:1 SR20VE motor with ID1000s in my S14 that's ready to fire up and dyno tune, but will not start and at best will only backfire a bit. Of course this is my first 'standalone' ecu and wiring setup with a conversion to SD using NismoTronicSA which is a MS based conversion of the factory ECU for pretty versatile features like hondata. I just HAD to swap to the much improved VVL head design with a stronger transmission to match the bigger turbo all at the same time with the electronics lol...now my worst nightmares are here, the season is done in less than 2 months and I'm not a fan of my amateur fun build not being driven for almost a whole year if any of you care to bother with suggestions.

I've confirmed fuses, grounds, optima redtop battery and starter to be good, IAT/ECT/MAP/TPS/CAS are all reading correctly with the maf disabled, no vacuum leaks, base fuel pressure @ 43psi (correct feed and return line routing), mechanical timing is correct with all 4 cylinders around 250psi so far, ignition timing is close to 15* without being able to run it up to temp yet (not that the CAS adjusted all the way to the other end makes much difference and the CAS cannot physically be installed improperly into the back of the cam as its tabs are offset), fuel injectors are not leaking and a few little pools of fuel are present in the chambers after cranking with good continuity to the ecu, NGK BKR8EIX or BKR7E plugs make no difference and have a bit of carbon, but no real heat getting into the leads, K20 Denso smart coil packs have a good ground & 12v source (deleted factory ignitor) with a strong spark outside the head and are firing in the correct order (coil pack and injector wiring changes only involved splicing on the new pigtails and worked perfectly on my previous ROM tuned DET with MAF setup) with configured dwell tables based on motec's numbers. ID1000 offset tables are calibrated. The pump gas sample does not separate and ignites well on the ground.

I'm trying to remember what else I've confirmed to be working properly, but I can't recall at the moment and it seems like everything beyond the tune seems to be where it should...looking at the tune which was conservatively based on a running & tuned SR22VET so if there's anything you guys notice in the screen shot of the data log (or other parameters I can add for your interest let me know), I'd surely take any advice on where you guys may focus.

It just feels like a fueling issue and roughly 7ms of IPW with 1% duty cycle seems low to crank it over, but I have little experience with this to be honest and the cranking tables show that it should be higher and even if I add fuel to the base map, it stays in that range in the data logs. The ECU is recognizing cranking mode which turns the injection to batch mode firing 1/2 the IPW twice per cycle until 1k rpm then on to being sequential. I thought it was wasted spark not the same for fuel, but I was wrong. I've disabled knock analysis not that it should have any affect and all the other compensations are either off or unrelated I believe. I could send the ECU back to be tested, but everything seems to be functioning correctly with good live readings. I confirmed 12v at the injector pigtails at IGN ON, but not during cranking so there could be a voltage drop there i guess or multiple injectors could be faulty however unlikely and they're not leaking ID1000s. I'm just running out of ideas and sick of chasing my tail.

Attached Files

Hi Tommy,

If the plugs are getting sooted from your cranking then there is fuel and you know there is spark.

Are the plugs ever wet when you've tried to start it?

I'd try pulling fuel out on cranking and see how that goes

I have noticed a little bit of fuel at one point or another on the plugs and can't remember pulling fuel out so I will give that a shot. thanks chris

I think you have too much fuel. I would expect 3 - 3.5ms or so cranking, and probably 2.0ms idling with ID1000s.

that's where my main fuel table is at in the very low zones, but this cranking table is throwing me off so hopefully it just takes some subtraction to get her going. thanks

I would tune cranking table after you dial in your main table if you can get the car to start up , warm up and idle. Can you post your calibration file and a datalog here, maybe we can help. If you dont get Injector PW then maybe you have an issue with the 20V CAS. I know John from JK Tuning personally and hes pretty good with helping people out with his NIsmotronic, since he is a busy guys his response time sometimes sucks but his tech support is pretty good. I have Nismotronic on my SR20VE B13 as well. What ecu are you using? S13 sr20det? You can email him the files and the info of the problem you have as well as post it here.

John is awesome and has answered a lot of my questions since I ordered nismotronic from him and we're going back and forth with this, he looked over my TCD & logs and made suggestions, but no luck yet. We may do a remote session soon, but I'm just trying to rule out possible issues that you guys can come up with lol.

I'm running the S13 sr20det ecu. I really hope it's not the brand new 20v CAS since that's an ultra pita to remove in a RWD while it is firing the coils in the right order and the RPMs seem pretty accurate at least that's all I've been able to confirm of its operation so far. I'll try a few more things and update this with a couple logs when I get to that computer, but I don't think I was able to upload my calibrations here before.

What about a fuel pump? can you see fuel pressure while cranking?

Yeah right around 43psi while cranking and the lines are routed correctly with the regulator after the rail

Fortunately, my startup company is doing very well so I don't feel like a complete failure lately lol, but I don't have as much time as I'd like to get this thing worked out and won't be able to get over to it for a few more days. I just thought I had all my bases covered and have really benefited from everything the HPA has put together. I just need to get over this hump and it's racking my brain.

Since the CAS is controlling spark and rpm correctly, it seems hard to believe that those signals it's sending to the ecu to control fueling as well are incorrect. Considering the months it took to get this 20v CAS from japan, I can't try another one easily and it's a major PITA to even remove it to have a look. I suppose a faulty ECU could be part of it, but the ECCS relays work.

Could the mechanical timing be off while having good compression across all 4 cylinders? Wouldn't the valves be opening at the wrong times and throw the numbers off? I can swap in some known perfectly functioning ID1000s as another alternative, but mine don't seem to leak and they do seem to provide fuel into the chambers. I'd imagine if they weren't producing a nice spray pattern, the engine would still be able to run, just not smoothly? Spark is still a crisp blue. I've done smoke tests and only had a few tiny pin holes that wouldn't cause anything major. Could some crazy air blockage I'm unaware of be causing this lol. I'm running out of ideas and it just feels like it's all there.

You say the coils are firing in the correct order, but I haven't seen that you have confirmed the ECU timing is correct with a timing light. I'm not familiar with your ECU, but most have a way of fixing the timing at 0deg so you can test with a simple inductive timing light (don't need a dial-back version). Crank the engine and make sure whatever trigger offset your ECU uses is set correctly.

You can be way off on fuel and still get an engine to cough and try to start.

But if the ignition timing isn't in the right cycle you might only get an occasional pop or backfire as the mixture ignites in the exhaust. The timing light test is how you confirm the ECU is synced to TDC of cylinder #1, however if you're in the wrong phase (ie, firing at the top of the exhaust stroke instead of the compression stroke), you may need to change your offset by 360 degrees.

Another thing that can bite you when an engine doesn't start, is the battery voltage is often too low while cranking because the battery has been discharged from so much cranking. Use jumper batteries, and charge the start battery between attempts with a good 10A+ charger...

thanks for reading. The 720cca optima redtop battery is cranking in the mid 9v and is often on a good snap-on charger so it doesn't get toooo low though I'd be happier with 10v+ cranking and the battery/starter tester confirmed them to be good. I did confirm with the timing light that the ignition timing is at least very close to 15*. I meant the right firing order by placing the coils and spark plugs near each other outside of the head against the intake manifold and cranking a few times to confirm the order at least and make sure the spark is a crisp blue. I wouldn't be surprised if the it's still firing at the wrong position in the cycle just because everything else seems to be spot on. I'm not sure how to change the offset other than flipping the trigger wheel in the CAS and even then, idk if that'll have the desired affect, but if I can access it, i'd be open to trying anything lol. This CAS is supposed to be a direct fitment piece, but I vaguely remember someone mentioning having to flip the trigger disc

I found 3 more diode lights to see what all four injectors are doing in conjunction with the coils and ALL 4 INJECTORS fire on every engine revolution. During cranking, the engine fires the injectors in batch mode which is like wasted spark so each injector fires twice per cycle, but only 1/2 the IPW (then goes to sequential after cranking ends or once per cycle @ full IPW)...mine are firing 4 times per cycle so I'm assuming something is backfeeding power somewhere...

I confirmed continuity from each injector pigtail to its ECU pin and I forgot the readings when I read voltage to each, but I don't remember it being out of the ordinary at IGN ON, but that was a little while ago. I'll confirm those tomorrow and check cranking voltage to each injector too, but at least I have another symptom to hunt.

here's a vid if this is actually a problem... https://www.youtube.com/watch?v=yJZzt1Z1vug

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