Intermittent shut off...

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
The fuel pump relay is located under the left front air scoop. It's the first relay on the left side.

According to the schematics, the TCI has an attachment to one of the coils (don't know which one exactly) and also the tachometer. That's why I'm thinking that the relay is taking some power from the TCI and it only shows up on one coil plug.

Now, I just looked at those same schematics, and you guys are exactly right. The VBoost controller also has an attachment to the TCI and only 1 coil. So now I see that the fuel pump relay is on one TCI/coil connection and the fuel pump relay is on another TCI/coil connection.

Now I have 2 things to unplug to see which one may be drawing down the number 3 plug voltage reading.

Hmmm, gotta get to work on this and figure this out.
Vinnie

i follow. but hey man, why are you chasing this one voltage as part of the issue?

its bringing it down on all our machines, gotta assume its normal? or are you hoping to eliminate the one drop by re-routing the electircal and hoping to get rid of the miss? that seems like an awful lot of work, i may go back to stock. had the misfire happen today while the bike was warming up. just died on me. started right back up and was fine.

Hey Jim, what COPs are u running?
 
I guess I'm chasing this thing because I don't know if this low voltage (which is apparently normal) but with the COP's, is causing the problem or not. But I like having the COP's and don't want to go back to stock.

What happened to your bike, with shutting off, has happened to me also. I was pulling out of a gas station and sitting there waiting for traffic, and it just died. Started right back up. Damn, I hate this but I'm glad it's not just my bike. Which tells me something may be able to be done about this. If it was just my bike, then I'd have to troubleshoot a loose wire or something.

I wonder if there are other COP's out there for other applications, like cars, that have a higher resistance rating more in line with the orignal coils? I'm going to start looking.

Vinnie
 
So i actually have '03 COPs re-reading my old messages as per Mark. which he thinsk they are mitsubishi. i'm wondering if we can get a consensus that its the R1 COPs that may be having problems. waitin gon Jim. so far it seems to be linked, but we'll have to see if more can chime in.

it also didn't seem to happen at first. more once the weather got colder. does that coincide with yours at all?

seems to be worse when the bike first starts up, or obviously at low rpms. more so linked to bike being cold i'd say.
 
I wonder if there are other COP's out there for other applications, like cars, that have a higher resistance rating more in line with the orignal coils? I'm going to start looking.

Vinnie


I'm not sure I understand how this is could help. If the problem is not enough voltage at this one cop (#3), how can increasing the resistance of the COP's help to increase the voltage?

If you increase the resistance, it will take more amperage to push power thru the COP. If more amperage is being used then less voltage would be available according to ohms law.

Then again, the issue may not actually be a voltage problem, maybe it is dependent on resistance only?

Have you ever compared the resistance of your COP's with someone elses that are working without issues?

Is there anyone out there running COP's that are not having any issues?? Danny?
 
Well I was thinking that with less resistance, the current increases and the voltage decreases. They are indirectly proportional. Like if you're running a machine that's designed for 230v operation, and you feed it with only 208v, the current increases and also makes the equipment run hotter.

I was thinking that the COP, plus what ever is tied with it (fuel pump relay, vboost controller), draws so much current, that the already low voltage may not only go lower, but draw so much current through the TCI, that is momentarily shuts off.

I have also noticed that my bike gets really sensitive not only at low rpm, but also in really humid conditions. I was on this ride and it was so damn foggy in th early morning. The bike kept stumbling on me, I thought it was going to be a problem for the rest of the ride. When it got wamer out and the fog burned off, the bike didn't do it for the rest of the day. So yeah, I'd say colder or more humid makes this problem worse.

Vinnie
 
I just read those articles on the R6 coils. I'm going to check my coils to see if there's any sign of arcing. They are R1 coils, but who knows. If I see any arcing evidence, then this could definitely be the problem.

Vinnie
 
vinnie.

mark is sending me a set of 'long' denso coils to swap out. shoudl have some definitive tests here. it got bad today. it didnt' want to stay idling at first, cold, cool afternoon. mid 50's. i may put the stock shit back in for the time being.

is there a good way to close the cracks on stock coils? epoxy? temporarily?
 
I'll bet if you dripped in some epoxy, the crack would be filled in just fine.
I really interested in hearing your tests with the long sticks.
Also, I kind of hate that there's this problem of ours, but it sure beats the hell out of thinking I'm the only one that has a problem and can't figure it out.

You guys ROCK for getting all this info to me. I was almost of the verge of purchasing a new TCI unit. Damn, that would have cost me a LOT of money for nothing.

Vinnie
 
Is there anyone out there running COP's that are not having any issues?? Danny?

Yeah, I'm running COP's on the '99 without any issues whatsoever....but I can't remember what year, or bike they came from. They are Denso's, I'm pretty sure.

I can check them and take the numbers off if anyone wants them.

danny

Garrett, Somebody said clear sylicone caulk will work fine on the coil cracks, just don't remember who it was.
 
well i have tons of silicone. that will be easy. well at least on the rear coils! haha. front ones are staying put, they're still in the bike

yea danny can u grab two readings? resistance of your COPs and the voltage tests we have been talking about?
 
I did some more testing tonight. I hooked up my volt meter to the #3 cylinder COP plug, and again I'm getting 10.3v only on that cylinder. All the rest are about 11.6

I unplugged both the fuel pump relay and the vboost control module. Neither made a bit of difference. So it seems obvious that they are not pulling down this plug's voltage.

This may just be the wiring in the TCI that shows up as a low voltage on #3 on the later model TCI.

Going to ride the bike this weekend with the soldered reg/rec stator wires and the direct to the battery hot and ground wires from the reg/rec. I'll see if the better charging voltage helps cure this issue. I have not actually ridden the bike since the wiring mod, now that I'm getting a full 14.2v just above idle. I have ridden since the new battery, and that seems to help a little, but not totally cure the low rpm occasional stumble.

Vinnie
 
Garrett, Somebody said clear sylicone caulk will work fine on the coil cracks, just don't remember who it was.

copy that. i'll get some mail sent off to u shortly bud!

I did some more testing tonight. I hooked up my volt meter to the #3 cylinder COP plug, and again I'm getting 10.3v only on that cylinder. All the rest are about 11.6

I unplugged both the fuel pump relay and the vboost control module. Neither made a bit of difference. So it seems obvious that they are not pulling down this plug's voltage.

This may just be the wiring in the TCI that shows up as a low voltage on #3 on the later model TCI.

Going to ride the bike this weekend with the soldered reg/rec stator wires and the direct to the battery hot and ground wires from the reg/rec. I'll see if the better charging voltage helps cure this issue. I have not actually ridden the bike since the wiring mod, now that I'm getting a full 14.2v just above idle. I have ridden since the new battery, and that seems to help a little, but not totally cure the low rpm occasional stumble.

Vinnie

honestly. for all this trouble i may just go back to stock or denso's. not worth all that ya know?

let me know what ya find out.
 
I tested the wiring to my #1 and #3 coils last night out of curiosity. My bike is still pretty stock including coils.

Cylinder #1
Key Off Key On
Orange .020 11.00
Red/Wh 11.39 11.37

Cylinder #3
Key Off Key On
Yellow 0.133 9.76
Red/Wh 11.34 11.33

Found the same deal as you guys with V drop on #3.
 
I think we can come to the conclusion that the voltage drop on #3 is normal (for the later model TCI).

Now I'm just thinking that the excessive current draw of 'some' of the models of COP's is just too much and causing the issues of the intermittent stumble at low rpm.

Next thing to find would be what COP's have the highest ohm ratings and use those. Plus I'll let you know after my weekend ride if my running the hot and ground from my regulator/rectifier direct to the battery, is now going to provide sufficient voltage to cure this problem. If we only need another .5v at the battery, then this mod could be the cure to provide sufficient voltage at the battery and then to the TCI. I mean if that's the problem. The reason I have always thought in the back of my mind that this was an issue, is that the problem was 1) worse with my old battery and 2) never apparent when running at higher rpms, where the battery charging was more effective.

The last thing that would most likely cure this issue once and for all would be going to back stock, like you guys also suggested. But I hate to throw in the towel just yet.

I'll let you know what I find out this weekend if the weather holds up.

Vinnie
 
few interesting notes this morning:

1. definitely worse at colder temps
2. definitely worse at low gears at low rpms. say going 15 mph and ur in like 4th gear. much more likely to happen. and dangerous.

infact, i am probably going back to stock tomorrow until the new denso's come in. its too dangerous to give it throttle and it stumble and then take off

took 3 tries for it to start up this morning too. kept dying on me. very frustrating.

on a side note, put some black silicone selant on my old coils so they'll be good to go.

Vinny, also on the ride into work i was thinking i dont think its nec a problem with one cylinders voltage b/c say that one wasn't getting enough just one cylinder dying wouldn't be enough to kill the whole bike like it was on mine, i don't think at least, so i def think its a whole system thing. and i think you also mean the lowest ohm rating not the highest, right?

in talking to mark:

Also, from what i've measured, the R1 COP's resistance are normally around 1.5-1.6Ohm where the Denso COP's are normally 1.2-1.4Ohm. Seen some Denso's at 1.5-1.6 but most are around 1.3-1.4


So thats the resistance of the COPs. Looking at the service manual, which measurement is that, primary or secondary?

And the primary measures the two plug tongs off of the coil, and does the secondary measure between one of those wires and the end of the actual spark plug wire?

Does the park plug wire coming off the coil add any resistance?

From the numbers primary should be 2.7, and secondary 13.2.

still not sure how resistance in the 1.3 - 1.5 range would make a difference? whether it be 1.3 of denso or 1.5 of R1's?
 
Well the higher resistance COP's shoud be better for this reason,,, The stock coils are rated about about 3.0 ohms. So the whole system is designed for that restistance. If you lower the primary resistance, then the whole ignition ciruit will pull more current.

The seondary resistance is not 13 ohms, but 13,000 ohms or so. So primary is what we're concerned with as that is what's hooked up to the TCI and ignition wiring and what's causing this whole circuit to pull more current.

If you take the same 12v and divide that by the COP's average resistance of say 1.5 ohms, you get 8 amps current draw. Double the current draw from the same circuit. The stock ignition fuse is rated at 10 amps, so we never blow the fuse, but I just still don't know if the TCI runs into a problem with the excess current draw, or a voltage drop inside. I don't just mean the voltage drop on #3. I agree that the COP's don't even come into play during our testing as they're unplugged and the bike is off.

So, using what's called 'Ohms law' you can see that small changes in resistance make pretty large changes in current draw. Figure 12v divided by 1.3 ohms,,,,,,,,,,, that gives you even higher current draw. 9.23 amps! And if there were COP's with 2 ohms resistance we'd get 12v divided by 2= 6 amps. The Stock sytem gives anywhere from 12v divided by 2.7= 4.44 amps,,, or 12v divided by 3.0= 4 amps. So if you had a stock coil with either 2.7 ohms or 3.0 ohms you'd be way lower current draw than our current setup with COP's running only 1.5 or 1.3 ohms.

This issue is most likely what caused me to totally blow up my Dyna 3000. It just wasn't designed to handle such a low resistance coil with such a high current draw. I used the COP's with the Dyna and it trashed it. Now I went back to stock and loved it until I saw this issue start up. I thougth it was something else on my bike, but now I'm seeing that we may have an issue on at least a few bikes out there running this setup.

I also agree with you that it's probably not just one cylinder dropping out. My bike feels like the whole bike shuts off. I once encountered it in a turn. Almost make me drop the bike. I gave it gas and she cut out, making me slam my foot on the ground because I wasn't expecting it and I didn't think fast enough to pull the clutch in. When it came back on, the bike took off hard. Dangerous to say the least.

All in all, if they made a COP with something closer to the stock 3.0 ohms primary resistance, then I don't think we'd be seeing any problems at all. Something with the low resistance of the COP's may be causing this, and like I said it could be such a high current draw, during times of low battery charging, that causes the TCI to cut out do to the total voltage drop within the TCI.

I'm really intersted so see if the charging system mod I did a couple of day ago, now putting 14.2 volts to the battery will help this. If not, then I'll be either going back to stock or searching for COP's with higher primary resistance whether they be designed for a bike or a car.

Vinnie
 
Well the higher resistance COP's shoud be better for this reason,,, The stock coils are rated about about 3.0 ohms. So the whole system is designed for that restistance. If you lower the primary resistance, then the whole ignition ciruit will pull more current.

The seondary resistance is not 13 ohms, but 13,000 ohms or so. So primary is what we're concerned with as that is what's hooked up to the TCI and ignition wiring and what's causing this whole circuit to pull more current.

If you take the same 12v and divide that by the COP's average resistance of say 1.5 ohms, you get 8 amps current draw. Double the current draw from the same circuit. The stock ignition fuse is rated at 10 amps, so we never blow the fuse, but I just still don't know if the TCI runs into a problem with the excess current draw, or a voltage drop inside. I don't just mean the voltage drop on #3. I agree that the COP's don't even come into play during our testing as they're unplugged and the bike is off.

So, using what's called 'Ohms law' you can see that small changes in resistance make pretty large changes in current draw. Figure 12v divided by 1.3 ohms,,,,,,,,,,, that gives you even higher current draw. 9.23 amps! And if there were COP's with 2 ohms resistance we'd get 12v divided by 2= 6 amps. The Stock sytem gives anywhere from 12v divided by 2.7= 4.44 amps,,, or 12v divided by 3.0= 4 amps. So if you had a stock coil with either 2.7 ohms or 3.0 ohms you'd be way lower current draw than our current setup with COP's running only 1.5 or 1.3 ohms.

This issue is most likely what caused me to totally blow up my Dyna 3000. It just wasn't designed to handle such a low resistance coil with such a high current draw. I used the COP's with the Dyna and it trashed it. Now I went back to stock and loved it until I saw this issue start up. I thougth it was something else on my bike, but now I'm seeing that we may have an issue on at least a few bikes out there running this setup.

I also agree with you that it's probably not just one cylinder dropping out. My bike feels like the whole bike shuts off. I once encountered it in a turn. Almost make me drop the bike. I gave it gas and she cut out, making me slam my foot on the ground because I wasn't expecting it and I didn't think fast enough to pull the clutch in. When it came back on, the bike took off hard. Dangerous to say the least.

All in all, if they made a COP with something closer to the stock 3.0 ohms primary resistance, then I don't think we'd be seeing any problems at all. Something with the low resistance of the COP's may be causing this, and like I said it could be such a high current draw, during times of low battery charging, that causes the TCI to cut out do to the total voltage drop within the TCI.

I'm really intersted so see if the charging system mod I did a couple of day ago, now putting 14.2 volts to the battery will help this. If not, then I'll be either going back to stock or searching for COP's with higher primary resistance whether they be designed for a bike or a car.

Vinnie

interesting thoughts. electrical isn't my specialty but i can follow.

mark made an interesting point, wondering if the mitsubishi cops, simply have a lower voltage limit, and at this low voltage on cold days or lower RPMs they don't fire b/c it's under this 'limit'?

could have nothing to do with resistance... thoughts?
 

Latest posts

Back
Top