jspaeth

Ok, so maybe this seems like an obvious thing to check, I dunno....

Now that I have the Splitfires (going in tomorrow), I decided to try pulling the rubber off of the bottom of the OEM coilpacks....I wasn't sure if you could do this, so I just pulled hard and it popped off:

This is what I found:









Notice the color of the metal ring around where the sprig/coiled wire comes out....

On 3/4 coilpacks, it is a copperish color.


On the top left one, the metal looks like tarnished copper....kind of bluish/greenish in color.



Does anyone know if this is a sign of anything?


Furthermore, I showed my dad, and we were discussing how far in the spark plug tip goes....

Does the end of the spark plug just touch the coiled wire and compress it a bit, or should the spark plug end push all the way in to the point where it is touching that ring of metal around teh coiled wire?



If the spark plug end relies on making contact with the metal "ring" around the coiled wire, then it seems obvious that there is some heavy corrosion or deposit or oxidation on the one coilpack and that this may be the issue.



If someone with knowledge of this could chime in, I would very much appreciate it.

thanks alot.

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jamanrr

A coil pack is a coil pack whether it is on an F150 or a sr20det. That oxidation is usually caused from mis-contact or the coil not being seated properly on the spark plug. Did you see the same oxidation or discoloring on the top of the plug where it made contact? If you did then it was probably arcing. This arcing can cause plugs to misfire and file out. You could use some OS cleaner or the like and a small file and clean it or replace it like you are doing. Put the splitfires on and see what it does.


oh yeah? do you use the 10 mm screws to hold the coil-packs in?

jspaeth

Of course I do....

However the one for the 1st cylinder is broken, so I put a piece of granite tile (decent insulator) on top of the coilpack and use the plastic cover to hold the coilpack down far enough....the graphite piece is more than thick enough.

IIRC, the one that had the weird color to it was NOT from the first cylinder anyway....


Justin


PS....do you know if when the spark plug gets pushed up into the coilpack....does it make contact with just the spring, or does it go up there enough to where the end of the plug actually contacts that "metal ring area" (the part where it is discolored on the one coilpack)?

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jspaeth

EPIC FAIL


Just put the new Splitfires in, and for the first 5-7 minutes, the car DID actually feel smoother, better idle and got 2-3 pulls in to redline (slow throttle) and the car felt nearly perfect.

2 minutes later, as the engine bay (presumably) started to get hotter, the car started misfiring in the high RPM regime (like 6K).

10 minutes later, I couldn't rev past 4200 RPM.

It's not fuel....I slowly revved up to 4500 RPM in 4th gear, and watched the AFR hover around the 14.0 mark, and it still hit 4500 RPM and was just not igniting (tons of backfiring and the car won't go anywhere).


UPDATED LIST OF WHAT I HAVE DONE

1) New coilpacks
2) Checked ignitor per the fsm and it passed all of the continuity tests.
3) Proven that the misfires occur independent of load or AFR but ARE dependent on RPM.
4) Seen evidence multiple times that the misfiring starts to occur about 10 minutes after the car reaches operating temp
- Does not have anything to do with the coolant or aire temperature, as I can monitor both of these and see that when the misfiring begins, there is no change in the IAT or coolant temp.
5) Fuel pressure gauge shows that FP is fine.
6) Grounds from head to chassis and coilpack ground are both grounded EXCELLENTLY to bare metal on chassis.


NEW IDEAS/WHAT I AM GOING TO DO

1) Put in new plugs today
2) Put in new spark plug well gaskets and valve cover gasket (very miniscule oil seapage previously....no droplets, just a residue/tiny film in a few spots).

3) WHAT ELSE COULD IT BE?????????????????

4) Try to open ECU and look for anything on the board that looks fried?



THE KEY ISSUE HERE IS THAT IT IS TRIGGERED BY HEAT. PLEASE HELP ME FIGURE THIS OUT, I WANT MY OLD CAR BACK!!!!!!!!

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driftintheS14

what plugs are you running? i have heard from numerous people that turbo cars do not like iridium plugsa at all and under boost they cut out, I have heard the best plug to use with turbo cars is a copper plug. anyone else ever hear of this?

i have a buddy that changed his plugs on his audi to iridium and was cutting out at high boost, put his old plugs back in and car ran perfect. also have found the same issue on 3 other cars

jspaeth

Already running copper plugs, but thanks anyway.

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jspaeth

Ok, here is the ignition page from the FSM:

I am trying to systematically figure this out.....




Working from the bottom to the top, taking into account that the problem begins WHEN the engine physically gets hotter (about 5-10 minutes after it reaches operating temperature of 80C or 185F)....

1) Ground in the bottom right (coilpack harness ground)....OKAY...grounded to firewall, bare metal.

2) Power wire (B/Y) coming from ignition relay.....OKAY....the car runs perfectly fine....other than high RPMs when hot....as far as I know, since the power is coming through the relay, this would either work or not work, but no "in between"

3) Coilpacks.....OKAY....the problem is STILL occurring, even with brand new Splitfire coilpacks

Provided the harnesses are okay (I have traced them as much as I can and don't see any exposed wires anywhere....the only two remaining things are

4) ECU....opened the ECU (PFC) and the board looks perfect, no spots no discoloration nothing wrong

5) Ignitor chip...doesn't get very hot sitting over on the intake manifold side of the engine bay, and it passes the FSM tests.

6) The actual tune......I have gone back and checked (4 TIMES!) to see if their is any differences between what is in the computer now and the last know "good" map (before this issue was occurring...) and I cannot find ANYthing different that would cause this issue.


PLEASE HELP



$5 PAYPALLED TO YOU IF YOU CAN FIGURE OUT WHAT IS WRONG AND HELP ME FIX THIS ISSUE!

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jamanrr

Throwing this out there as something you should check since it is known to happen. The main relay if it is or has a intermittent heat problem could be bad in that once it gets hot it will cut in and out. Do you or have you every experienced any problems with starting the car when this occurs or when it gets hot?

jspaeth

YES! After the car heats up or whatever and goes through this process (misfiring above a certain RPM)....when I get home and turn the car off...

If I try to start the car immediately thereafter, it is nearly impossible to start.

I understand what you are saying, and I will certainly give it a shot (swap it with another relay), but how is the heat getting to a relay that is located over in the passenger side kick panel...and if the relay was intermmitent, wouldn't it be less predictable than what I am seeing (sputtering/misfiring occurs above a particular RPM)


....you are referring to the main ignition relay, right?

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jamanrr

right it happens on Hondas all the time. If I remember correctly the relays will develop cracks in them and then when they get hot or have heat in them they will have an intermediary problem. Just replace it and see if it helps. Additionally, do you hear your fuel pump prime when you have trouble starting the car? Yeah the main relay.

Not if it heats up or if the circuit board within the relay has micro cracks within them. Then when it heats up and does its resistance thing, the connection becomes funky and not 100 percent. make sense?

jspaeth

i am like 99.99999999999999999999999999999% sure it is ignition related and not fuel.

will swap it with another relay tomorrow and give that a shot.

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jamanrr

yeah report back afterwards

Z U L8R

i highly doubt the ignition coil relay is your problem because it's probably not even there, nor needs to be.

you would be the only sr owner i have ever seen in 12 years have a sputtering problem caused by this. either they didn't wire power to the coils and the car didn't start, or it's wired in and that's it.

your power supply for your ignition coils are probably tapped off of your switched ignition 12volt power supply (black/red) wire, which is how 99% of sr swaps are wired up.

in japan from the factory there is a separate ignition coil relay.....i highly doubt your swap has that, or is the problem, because it's not a problem on anyone elses car.

at this point, you should get your car on a steady state dyno where you can log and inspect everything while it's acting up, then you'll be able to determine what's really going on and fix this problem.

i still think the problem is in the tune,

my .02

Dave

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jspaeth

Dave, I do respect you....but I believe YOU don't trust me on this one.


The tune I am using has worked perfectly fine for 10 MONTHS in a row, never having ANY misfiring issues.

How is it the tune? A tune that is not good doesn't just randomly cause misfires after 10 months.

Furthermore, I ahve stated dozens of times that I can watch the AFR gauge and the problem happens at the same RPM, regardless of how much load is on the engine or what the AFR is.

Even yesterday, I was barely putting my foot on the throttle in 4th gear on the highway and at 4000 RPM in vacuum, the AFRs were like 14.0 and the car started misfiring as soon as it hit like 4200 RPM.

It is a bit frustrating when people say "it's the tune" or "check the fuel pressure" or stuff like that. I am not the world's best car person, but I really do understand all of this shit and have tried to very clearly present all of the steps I have followed and things I have checked.

I am about 99.99999999999% sure at this point that this is ignition related.


Dave, is there anything that you can think of that is IGNITION RELATED that would start causing misfires once the car gets hot (about 10 minutes after the coolant reaches 185F or so)?

A key thing here is that once the car warms up, it runs fine and revs out to 7500 RPM no problem....at this point the ECU is getting certain signals from sensors (coolant temp, air temp, etc).....5 minutes later, it is STILL getting the same signals from these sensors, but then it starts misfiring, and it gets worse with time.

I should add that after this happens, if I turn the car off, it is nearly impossible to start.....

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jspaeth

Okay, well the problem is now getting worse with time, and is still "heat induced"

It now starts stumbling around 3700 RPM and fully misfiring around 4000 RPM.

My dad came for a ride with me, and we both agree that there is potentially a full "across the board" misfire....

The car stops pulling so abruptly that it seems like it can't be a single cylinder misfire.


THe fact that it is heat-induced and getting worse makes us think that it is an electrical connection....

Like I said, the ECU board looks okay, and things shouldn't really be getting very hot in the kick panel at all.


I am leaning towards ignitor chip now........if anyone can get me an ignitor chip for a reasonable price, I would really appreciate it (perhaps people doing VE heads swaps that are using a distributor now?)....

I am going to try to open the ignitor chip (probably a pain in the ass....) to see if something is wrong.


My dad (E.E.) thinks maybe it's possible that the single ground wire coming into the ignitor chip could have a bad (and getting worse with heat) connection inside, causing the across the board misfires.


Does anyone know what the circuit INSIDE the ignitor chip looks like?

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2fast4y0u

damn dude, i have been gone for a few days and am just catching up.

check your tune... jk

this might sound crazy but could it be a coolant temp sensor, or something like that? i dont know a ton about this but, dont our car go through loop cycles? i might be using the wrong terms so bare with me.
start the car, it goes through a closed loop cycle..then after it warms it goes through another loop cycle.
i know i might sound crazy right now, but maybe that will steer you in the right direction.


side note: for it to be heat related, its something that has to be getting awfully hot...maybe check all your connectors that are near the block and also the wiring near the block.

Z U L8R

if we go with plan b....

could be the igniter, cam angle sensor, or could also be the maf (if you have one).

sometimes you don't get lucky with the typical can't rev passed 3k symptom. i've seen maf's make the car sputter, cut out, and die after 5-10 minutes of driving, then the car start right back up. or in your case the car hard to start.

datalog your rpm in graph mode like an osciliscope and if you see the rpm data breaking up then you can determine the cas is the culprit, or deduce it from the possible problems.

you should be able to identify the problem by datalogging.....

if the car's breaking up and everything being logged looks absolutely perfect then we can do other tests to deduce the problem.

gl,

Dave

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jamanrr

Yes. this is the reason I always clean MAFs especially Nissan's. Had a Supercharged Frontier and it was sputtering and running like ass so I cleaned the MAF along with replacing a couple of O2 sensors. The same with the 240, I make sure my z32 maf is clean. They make Mass Air Flow cleaner.

jspaeth

Thanks for the suggestion guys.

This is a Power FC, D-Jetro.

I can see, on the screen, both coolant and air temp. Both are constant....not causing the problem.

Ideally, I would like to see what is going on with the CAS.

My money is on ignitor or CAS.....I have an ignitor coming in the mail which I am going to test out next weekend....until then, the issue is on hold....left the car at my parents house and borrowing my brother's car.


It is definitely spark related, not fuel.


After the car is turned off, I can't start it up again (when it's hot and the sputtering problem has been going on).....however, the fuel pressure is fine during cranking (FP gauge).


This is clearly ignition. It is either CAS or ignitor I think.


As said 100X already, the car runs PERFECT after it warms up....then 5-10 minutes later, the misfiring starts kicking in, and it gets worse with time.

After about 20 minutes of driving, the car was starting to misfire as early as 3800-4000 RPM.


As far as I am concerned, this almost surefire evidence that the issue is being caused by HEAT getting to something.....

And because of how the ignitor and CAS work and how heat could effect each one, my money is on a bad connection inside the ignitor that is getting screwed up as things heat up and expand.

We'll see next weekend!

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jamanrr

did you check the ignition relay on the passenger side? I can hear it clicking when I turn the key to the on position. If you do not hear it fully click or engage it could also cause problems usually with the car not starting.

veloz

So I read through much of this thread and find it interesting.

I have a S14 Silvia - Full VTC,
Full Boost and Torque @ 3500 RPMS,
GT2860RS running 16 lbs - 300hp/300WTQ @ 11.5 AFR across the board
Stock Coil packs...BKR7E
NISTUNE

I had a bad sputtering like that once.
I Changed plugs like 1 MILLION times and would do it pretty much any time. I tried bkr6e, bkr7e, irridiums, v power, flat, etc.


It might not be your issue, but it's out there.

The coils WERE grounded to that little strap on the back of the valve cover. Very SMALL gauge Wire.

It MELTED the ground and I could see it smoking.

I redid the grounds on the entire car, and specifically re-grounded the main coil harness and rewired it and it went away.

If the problem got worse with the SPLITFIRES, You could try re-grounding each coil individually or at the very least redoing the ground.



Also, please change your plugs after your car runs like ass. If you foul them, you may not know if something has helped or not.



Just recently, I was competing in a Time Attack and my car sputtered at 6K like you are saying.

It cost me a podium hence I'm looking up the issue.

I did notice that the problems were worse when it was hot. My issue may be old coils or heat related.

Good Luck.

jspaeth

Thanks for your response.

The coilpack harness ground is now coming off of the splitfire box/module, and is grounded VERY well to the firewall, bare metal.

The head is grounded VERY well to the firewall, also bare metal.

The grounds for the ignitor are grounded to the intake manifold (have been for 5 years) and the manifold is grounded to chassis very well.

None of the grounds have changed at all over the past 5 years, and I see no evidence of melted wires or anything like that.

I am praying the ignitor chip is the issue.

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xska

Remove CAS and spin the shaft, it should be constant resistance both way.
but if it spins free and drags, most likely bad bearing causing timing to jump up and down.

jspaeth

If the ignitor doesn't fix it, the CAS is next on my list.... I fail to see why there would be a CAS related issue that gets worse with heat.

Furthermore, the RPM at which the misfiring occurs has gotten lower and lower (used to be 6000, then 5000, now 3800-4000).

But....the car runs fine for the first 10-12 minutes after it is started.

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xska

Heat expands bearing...?

jspaeth

Possibly, but I honestly don't see that being a likely cause...the CAS will be the next thing I check, like I said,

But it sounds like it is getting NO spark or WEAK spark.....not "wrong-time" spark.

Also, once the problem kicks in, the car is nearly impossible to start....what type of timing does the car use when it is cranking?

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xska

It should be between 0-20 btdc.
On L-jetro power fc, 3 or 5 btdc is on base map, but on D-jetro it maybe running off what's on first column, 10000 load.

jspaeth

Okay so you are saying it will basically read off of the lowest RPM column and the row corresponding to atmospheric pressure....that is what I would have expected....

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VNG704

Just a guess, but I think the bolts that hold down the coil packs are also grounds for the coil packs. How did I guess this? Well I have the Sun Auto Hyperforce ignition thing and the wire harness for it has 4 ground wires that I ground to each of those 4 bolts that hold down the coil packs. Other wise why would Sun Auto have the grounds set up like that? Instead of one ground wire to chassis, know what I mean? So your problem could be that one missing bolt/ground. Try getting a bolt for that missing one.

Someone correct me if I'm wrong.

Z U L8R

dunno bout hyperforce coil packs, but the stock sr coil packs and the splitfires don't have to have the bolt there to ground it. it's there to just hold the coil onto the plug.

i was pretty sure you were d-jetro but i didn't feel like reading back through 3 pages lol which is why i said "(if you have one)" speaking about the maf.

because the problem has been getting progressively worse it does sound like a failing part slowly taking a crap, but like i said, if you can just log the rpm on your next test drive, datalog when it's sputtering and if the rpm log doesn't mimic the sputter or doesn't randomly cut out then you can pretty much deduce the cas as not the problem.

i know the car's at your parent's house so you can't go outside and do it right this minute, but log the rpm feedback on your next test drive when you pop the new ignitor in there.

gl, you're almost there.

Dave

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