TCI Bad on '03?

VMAX  Forum

Help Support VMAX Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

infinity999

Well-Known Member
Joined
Oct 31, 2009
Messages
66
Reaction score
0
Location
Las Vegas, nV
Well I have an '03 and it is currently running on two cylinders. I can pull the plug wires on 3&4 and the bike doesn't stumble etc. I checked (with a meter) the easy coil to get to which is the one under the seat that fires cylinder 3 and it checks good. Service manual says if that's so then replace the TCI. Any suggestions? I see nothing in the service manual about testing the TCI to see if it is faulty. Carbs were recently gone through by Dannymax so I know they are functioning property. Thank you for suggestions.
 
I would say to test the wires going to the coils, and if they test out I would try swapping the coils around.
 
its happened quite a bit before you weren't doing any work up front and plug the coils in backwards on the front cylinders eh? they go the opposite way you'd think.
 
Well I verified that coil #3 is good by using it to run cylinder #1. The only other things that are really left are the TCI or the wires going from the TCI to coils 3&4. How difficult is this thing to remove? The TCI that is (so I can check the wires going to the coils).
 
Did you check the power feed going into the coil to see whats going on there?

Did you test the pickups?

Its only 1 pickup so if the other 2 cylinders work the other two should as well. Check connectors, both on coils and TCI. Check HT leads especially the tip that connects to the coils, the wire may be corroded and not passing the HT properly. You can try to put #1 coil to fire #3 cylinder and vice-versa and check if the problem passes to #1 cylinder or remains in #3 cylinder. Then you can check if its a problem of ignition or carbs...
 
Its only 1 pickup so if the other 2 cylinders work the other two should as well. Check connectors, both on coils and TCI. Check HT leads especially the tip that connects to the coils, the wire may be corroded and not passing the HT properly. You can try to put #1 coil to fire #3 cylinder and vice-versa and check if the problem passes to #1 cylinder or remains in #3 cylinder. Then you can check if its a problem of ignition or carbs...

Looks like he already swapped coils around

Well I verified that coil #3 is good by using it to run cylinder #1. The only other things that are really left are the TCI or the wires going from the TCI to coils 3&4. How difficult is this thing to remove? The TCI that is (so I can check the wires going to the coils).
 
I think you are on the right track. If you can borrow a black box for testing, that would be ideal.
You can test the wet float levels with it running to be 100% sure it's not a fuel blockage. Or spray aerostart around the carby rubber in case it's got 2 split rubbers. As suggested, check coil wires and connectors too.
But yeah, it's sounding like ignition module could be it.
 
Think I've finally figured it out. I was messing around with the plug wire for #3 and was shocked and saw the arc coming from the wire. I assume this is what is going on with cylinder #4 also. Ordered a set of wires. Thanks for all your help and advice. I learned a lot about troubleshooting the ignition system.
 
Pleased that you have found the problem - it's usually the simple things that fail.

This article on testing COP's may be of interest.
In particular the test procedure for the switching circuit on page 4 not only applies to those with COP's but all Maxii where an ignition unit is suspect.
 
Think I've finally figured it out. I was messing around with the plug wire for #3 and was shocked and saw the arc coming from the wire. I assume this is what is going on with cylinder #4 also. Ordered a set of wires. Thanks for all your help and advice. I learned a lot about troubleshooting the ignition system.

Wel that is good news! :eusa_dance:
 
Well I was hoping the new plug wires would fix my issue, but they haven't. With all the new wires, I can still pull a wire from cylinder 1 or 2 and the bike dies. Pulling a wire from 3 & 4 does nothing to the idle unless the bike is choked and over 3k rpm or so. I know 3 & 4 are getting some kind of spark and I know that the coil on at least cylinder 3 is good because I swapped it with cylinder 1. Also, the mixture screws on carbs 3 & 4 do nothing also which indicates the bike is not running on those two cylinders. At least at idle anyway. I know 3 & 4 are getting some spark because when I pull the wire and I touch the engine I can feel it. Maybe it's not strong enough? Can the TCI be weak? Really not sure what's going on here, any help is appreciated.

Update: With the bike choked I can pull the wires off cylinders 1 & 2 and the bike will run with cylinders 3 & 4 connected. So it's either a weak spark or there is something wrong with carbs 3 & 4.
 
Dannymax synced them after he set the floats. Put the carbs back on a couple of weeks ago and the sync looked good to me.
 
i'm coming in late here but what do 3/4 plugs look like?

i'm sure sean has a bunch of parts he can send you on his electrical loaner program.
 
Patrick, was it this running issue that prompted you to remove and clean the carbs initially, or did the problem show up after the carbs were re-installed?
 
Did you sync them on YOUR bike? If not each engines demands (and each cylinders demands) will make them not be correct on a different engine.
 
Back
Top