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Ricer240sx 11-10-08 03:02 PM

starting problems....spark issues again!!!
 
hey guys, so yeah, finally got the dough together and had my motor rebuilt and ported by banzai racing, got it back, in the car and all hooked up and ready to go and.....doesnt start :( i smell fuel so im sure its getting fuel, dont know how it wouldnt be getting air, so leaves me to no spark....pull the wire off one of the leading plugs and throw a plug in it and ground it, crank and nothing. as soon as i stop cranking though it lets off a spark..... i swap out the cas thinking it might be that....spin it while out of the motor and i get spark...sweet pout everything back together exept for the plug wire and crank...again nothing! last time this happend it was doing the same, but once i corrected my mistake on my coil mod (running FD Power FC) i got spark and the motor fired up (how i realized i was once again screwed over on a motor purchas and led to teh banzai build which is not in question at all in this issue obviously)

so i go to my FSM and do the only 2 checks i can ( check voltage across the 2- prong connecots and resistance across the coils) on each of the coils, primary checks out fine, on the secondary the resistance of the coils is good but the voltage across the 2 prong connector ( from black/yellow wire as stated in the FSM) is only registering about 8/9volts......so obviously my problem is somewhere before that ......but wondering if anyone had any similar issues and could hint me at some shortcuts as i donot have a heated storage unit and i dont feel like sitting out in the cold tracing the whole harness back to find whatever it is im looking for.....

sorry for the long read and thanx to thoes that help out

also, where can i get a igniter checker so i can check that as well, or would that be pointless now that i modded the coil/igniter to work with th FD PFC????

Banzai-Racing 11-11-08 06:06 AM

You have a wiring/grounding issue or an ignition switch problem. When you turn the key to crank the engine you are cutting the power to either the ECU or the coils. This is why when you let off the key you get one spark from the plug. It could also be a very weak battery, when you engage the starter it draws down the voltage, potentially you do not have enough voltage to keep the ECU powered up while cranking.

You only modified the trailing coil. The only way this will effect the leading coil is if you wired the power wires incorrectly, which could short out the whole system. The car does not need the trailing coil to start up, so disconnect it from the harness and see if you have spark on the leading plugs while cranking.

Do you have the trailing and leading coils bolted in the car? The bracket must be fastened to gound or the coils will not fire.

Ricer240sx 11-11-08 09:03 AM


Originally Posted by Banzai-Racing (Post 8711236)
You have a wiring/grounding issue or an ignition switch problem. When you turn the key to crank the engine you are cutting the power to either the ECU or the coils. This is why when you let off the key you get one spark from the plug. It could also be a very weak battery, when you engage the starter it draws down the voltage, potentially you do not have enough voltage to keep the ECU powered up while cranking.

You only modified the trailing coil. The only way this will effect the leading coil is if you wired the power wires incorrectly, which could short out the whole system. The car does not need the trailing coil to start up, so disconnect it from the harness and see if you have spark on the leading plugs while cranking.

Do you have the trailing and leading coils bolted in the car? The bracket must be fastened to gound or the coils will not fire.

thanx ill have to check that out after work...pretty sure batt is good though i leave i on the charger while checking everything and bumped it up to the start setting too to make sure i had enough power but ill throw the voltmeter on her and crank see whats up...its not the factory batt so ill have to check the rating on her make sure its good....

Ricer240sx 11-17-08 04:58 PM

bat voltage confirmed at coils while cranking as well.....i checked the ecu too but accidently down loaded the wrong pin out so i didnt have the full thing, but ignition power stays bat. volts as well.....idk, its prolly something right in my freakin face too!!!!

Ricer240sx 11-17-08 05:00 PM


Originally Posted by Banzai-Racing (Post 8711236)

You only modified the trailing coil. The only way this will effect the leading coil is if you wired the power wires incorrectly, which could short out the whole system. The car does not need the trailing coil to start up, so disconnect it from the harness and see if you have spark on the leading plugs while cranking.

.

disconnect both th e2 pin and 4 pin connectors or just the 2 pin?? i have the same results from just the 2 pin disconnected

Banzai-Racing 11-17-08 05:51 PM

Does the commander stay lit up while cranking? You have verified that you have 12V at the coils while cranking, now you need to verify that they can actually get a signal to fire. The coils, just like the injectors, see positive voltage all the time, the ecu grounds them to get them to fire. If the ECU is turning off while cranking then it will not start.

You need to verify that you have grounds at 4A ,4B, 4C, 4D and 12V power for the 1A and 1B on the PFC
PFC grounds connector #4

4A = S4 3A
4B = S4 3G
4C = S4 2R
4D = S4 2C

12v PFC connector #1

1A = S4 3J
1B = S4 3I

Do you have another CAS? Plug it in and spin it, see if you get spark.

Ricer240sx 11-17-08 06:12 PM

yeah i have checked with a second cas and both fired the plugs when spun

i will check the rest tomorrow!

Ricer240sx 11-19-08 04:01 PM

checked ecu and got grounds and 12v where specified....didnt check while cranking though as im workin by myself without use of my right thumb :( workin on getting some assistance from someone though

Ricer240sx 11-29-08 09:34 PM

could i run and n/a harness on this pfc??? i have one that is in better condition than mine and im lookin to swap out...but if not ill just replace the necc. plugs.....

pauli311 11-30-08 01:01 AM

When you say the coils have to be bolted into the car, do you mean the actual coil packs themselves have to be screwed into the cradle thing? I have mine mounted up on the driver's side and perhaps this is part of my problem since I smell fuel and the only thing different right now is the coil packs aren't bolted in place.

Banzai-Racing 11-30-08 07:46 AM

Chuck- Yes you can use a N/A harness but there are a couple wires that you will have to run, Alt to the ECU being a biggie, it is well covered on this forum

Pauli311-The igniters need to be bolted down to a ground for them to operate, the OEM FC coils are attached to the igniters

Ricer240sx 11-30-08 01:46 PM

pulled the intake mani of and played with a couple connections, checked the resistance at the cas (it is within specs) and put it back together and threw a diff batt charger on her, threw it on the start setting and cranked, now it starts sparking for a sec or so then stops........gunna try the batt out of my subaru i guess and see if the batt. is jacked up or something.... im using an Odyssey PC 680MJT slim battery...says its rated at 680 cca which should be more than enough i believe... but im getting closer and WILL figure this thing out!!!!!

Ricer240sx 11-30-08 02:16 PM

ok tried the stock ecu again and this time with the batt from my suby... got her to fire up!!!!!! but killed it after i taped the throttle, but theres no maf and 720/1600 inj so i guess thats not supprising lol also the tach was not registering anything the whole time, never while cranking or after i got her to run.....ideas???

Ricer240sx 11-30-08 02:22 PM

also the PFC comander doesnt register rpm while cranking....

Ricer240sx 11-30-08 02:48 PM

hey banzai, u wouldnt happen to have a map for a stock fd at all would u?? i wanna find someone with a fd to hook the PFC up to to see if maybe its the PFC and i only no one guy but all he has is exhaust so if i cant get his car running with it pluged up then i no where the problem is...

Banzai-Racing 11-30-08 02:50 PM

With the rewired trailing coil, the stock ecu will not provide a tach signal. It will not stay running without a MAF and the boost sensor is not correct.

If you are not getting a tach signal on the commander while cranking then it is not seeing the CAS.


Just reset it to default, that is the stock FD settings. I think that is a great idea, because it sounds like you may have bought a fried PFC.

Ricer240sx 12-04-08 02:19 PM

also, is there a way i can check my coil mod with a multimeter to make sure i didnt jack that up??? i already found out the two brown wires were jacked up... but what i dont understand is after i fixed that i got the last motor to start up and now all of a sudden i cant get the damn thing started and im getting no signal from the coil to the PFC.....i never removed the PFC and not sure how i could have fried it....maybe a ground is out of place or something, i was told there reall ypicky about grounds... i do have both coils mounted and the nuts tight......ugh, i hate electrical problems!!! lol

Banzai-Racing 12-04-08 02:34 PM

Yeah, I am the one that told you about the grounds in post #6. Having the wires "jacked up" initially could have fried the ignition portion of the PFC.

Check the grounds on the block.

Ricer240sx 12-04-08 03:37 PM

but if it worked after i fixed my mistake that would imply that the PFC is not fried correct?

Banzai-Racing 12-04-08 05:11 PM

Box it up, ship it to me and I will plug it in to one of our shop cars and see if it works. Include return shipping in the box. That will put an end to that mystery.

You cannot base anything off your last engine, remember I have seen the internals.

Banzai-Racing 12-04-08 06:06 PM

Send your coil pack too, so I can inspect that. Package everything so that it doesn't get damaged, ship them in two different boxes if you have to.

Ricer240sx 12-05-08 07:23 PM

so, i found out that the bolt i used for the ground coming off the engine harnees was bottoming out in the hole and the ground wasnt tight at all! fixed that but currently have no batt to test her out with....

also, say i put the COR wire on the engine side instead of the dash side as stated in the install instructions...would that cause this????

not sure if i did or not though im not at the car, but it was suggested to check...also which pin is the COR wire coming from, i nolonger have them labled....and what do u mean by dash side/engine side?? are u talking 2 diff harnesses?? if u could please let me know more specificly...again im not near the car so i cant take a look at it right now, but yeah, hopefully ill get a batt for tomorrow and can finally get things figured out!!

also, with that base tune, if im not connecting the i/c piping and there for not boosting what-so-ever, will i be good to do my break in with that yet or do i still need to tune it some??

thanx for all the help, oh and for the xmas card!! thats awesome!!!

Banzai-Racing 12-06-08 05:27 AM

COR is circuit opening relay, if you hear your fuel pump prime when you turn the key then it is hooked up correctly, it has nothing to do with the ignition coils.

I would hook up the IC piping so that you do not overspool the turbo.

Ricer240sx 12-11-08 07:40 PM

so, got it to start today on the PFC!!!!! whoot whoot!! but then it died and wont start again....for some reason its intermitenly sparking and i had to use starter fluid the one time it did start....i no the 2 grounds i fixed are tight...i also cleaned off the mounts for the coils with a wire brush before it started as thats how they ground...now all i gotta do is either find out what batt to run or where i have a loose ground at....for some reason though i remember having one more ground to the engine but i cannot find it on the harness....bleh sooooooo close yet still so far...lol o well im still siked cause im closer!!!

ElitetunerzRx7 12-12-08 04:07 PM

More Starting Problems Help!!!!!!
 
engine ground?? not sure why its intermitant unless it is a loose wire or ground thats gettting shaken. id go through every possible thing sparkwise and groundwise front to back and just reconnect them all as tight as you can. your bound to find it somewhere.


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