TCI Computer

[vince95]

How often does the main TCI computer go bad? I would imagine they are pretty durable. I have gone thru most of my bike without finding any problems. Here's the story.

My bike ran fine a few months ago and then all of a sudden it started running like crap like it was running on 3 cylinders. Felt like it lost most of its power. The next day I tried to start it and it will not run without choke at all. Once warmed and choke taken off it died. I had a spare carb set (brand new carbs) changed out and it ran without choke but popped once warmed up and had a miss out of one of the exhausts. Also at idle bike goes from 1k to 3k out of the blue. Also when blipping on the throttle, response laggs and also sometimes goes to high idle without coming back to 1k. I have tested pressure sensor, vboost seems fine, have tried disconnecting vboost and still the same. Can here what sounds like a momentary clink or hestitation in the airbox/carbs - not sure what that is but had this in the past with older carbs - dealer said it was carbs and cleaned and charged me 900. Still had this later on but never really affected anything. Even the new carbs do this so maybe thats the vboost butterflies - not sure???

Have done the usual - checked for vacuum leaks with carb fluid. No leaks detected at boots or manifold. Have changed fuel filter. Airbox tight and fliter clean and all screws tight too. Found one coil with some corrosion replaced and other 3 coils checked good. Replaced spark plug wires, spark plugs. Cleaned carbs and set at 2.5 turns out. Checked all boots tight. Also changed rubber lines. New carb boots and new rubber caps for the sync covers. Also synced carbs. Pickup coil check good resistance at 100 ohms. Stator checked good. Ignition systems seems ok.

I am running out of ideas but believe I have checked everything good expect for the main TCI compturer. I do have a couple electrical parts on the way that I want to try to swap just in case. Main computer and a vboost contoler box. Question - does the vboost controller box also control ignition firing in addition to the vboost control? Or is the TCI the main controller?

 

[satariel666]

85-90 TCI's really sucks and not much reliabe.
I have a friend localy who had exactly the same. Fireing only with 3 cyl.
Ignition coils power switching transistors were bad.
I've succeed with repair his TCI with Seans help couse it no way to buy those transistors here. Sean bought and send me some. I've also fixed one of his TCI.
Got two from him but one was badly burned inside.

You may look here:
http://www.jetav8r.com/Vision/TCIRebuild/TCI_Rebuild.html

You may talk to Sean about his exchange program. Not sure he still have this fixed TCI.


Pre 90 ignitoin boxes were analog and post 90 were digital.
Post 90 TCI's are very strong and hard to burn, altough pre 90 ones are very easliy to be fried.

 

[vince95]

:bang head:

85-90 TCI's really sucks and not much reliabe.
I have a friend localy who had exactly the same. Fireing only with 3 cyl.
Ignition coils power switching transistors were bad.
I've succeed with repair his TCI with Seans help couse it no way to buy those transistors here. Sean bought and send me some. I've also fixed one of his TCI.
Got two from him but one was badly burned inside.


Thanks for the info.

My bike is a 1995 and I do have a used one on the way that I hope is good. I just tried rebuilding and making sure my airbox is airtight. Still runs like crap and smokes really bad now out the exhaust on start up. I have almost 1500 into it and no fix yet. This is getting really expensive and frustrating. :bang head:

 

[Birdoprey]

What color is the smoke? From your description in your first post, i would think it was fuel related. I know you've looked at that, but its still what i would think vs ignition. I don't think the TCI would cause the idle to go from 1K to 3K.

 

[one2dmax]

I've got a few good newer TCI's anc can send one and any other parts you need on the testing program. Buy it if you need it.

Sean

 

[satariel666]

Thanks for the info.

My bike is a 1995 and I do have a used one on the way that I hope is good. I just tried rebuilding and making sure my airbox is airtight. Still runs like crap and smokes really bad now out the exhaust on start up. I have almost 1500 into it and no fix yet. This is getting really expensive and frustrating. :bang head:

Ooppss i've just looked wrong at your v-max year. I tough i was not 95 but 85, DOHH!

So you have newer TCI and personaly i've never heard of fried new type TCI.

 

[vince95]

What color is the smoke? From your description in your first post, i would think it was fuel related. I know you've looked at that, but its still what i would think vs ignition. I don't think the TCI would cause the idle to go from 1K to 3K.

Smoke looks to be blue grey in color. Would a fuel related problem possibly also cause a missing/popping out of one cylinder?

 

[KJShover]

Smoke looks to be blue grey in color. Would a fuel related problem possibly also cause a missing/popping out of one cylinder?

grey smoke with a blue tint to it is a sign of oil burning in the chamber. You may have some leakage or some blow by happening. What did the plugs look like.

 

[vince95]

grey smoke with a blue tint to it is a sign of oil burning in the chamber. You may have some leakage or some blow by happening. What did the plugs look like.

Here is a picture of the plugs:

 

[KJShover]

The two on the left look fine a tad rich even, but looks good.

The lower right looks like a new plug.

the upper right looks to be fuel fouled to me, not oil fouled. Maybe a carb issue.
How do they smell? oily, fuelly? ashy?

 

[vince95]

The two on the left look fine a tad rich even, but looks good.

The lower right looks like a new plug.

the upper right looks to be fuel fouled to me, not oil fouled. Maybe a carb issue.
How do they smell? oily, fuelly? ashy?

They have a slight fuel smell. The carbs are brand new and had the a/f covers still on. I drilled them out and all were 4 turns out from the factory. I adjusted to 2.5 turns out. Bike still ran rough with the popping out the exhaust on the left. Cylinder is the left rear.

 

[KJShover]

They have a slight fuel smell. The carbs are brand new and had the a/f covers still on. I drilled them out and all were 4 turns out from the factory. I adjusted to 2.5 turns out. Bike still ran rough with the popping out the exhaust on the left. Cylinder is the left rear.

The smell is normal, a tad bit rich.

Thats wierd that all the a/f screws were 4 out. normally they differ from carb to carb from what I've seen. see if you can't give em a sync to give you a starting point.

However, The most common thing for popping in the exhaust is excess air. It 's either too lean or there is an air leak in the exhaust somewhere. The pops are when fuel left over from poor burns ignites.

Have a look see at your boots, fittings and exhaust fittings. See if something has come loose and is introducing more air. We all know how the Vmax's carbs hates air leaks.

From there I'd check the boots and plug wires. I'm still thinking atomization issues. easy and cheap to check, before ignition pieces are bought.

Hopefully Sean, Mark, Fargo or someone with a little more exp. will see this and jump on in and help with some suggestions.

 

[RagingMain]

The smell is normal, a tad bit rich.

Thats wierd that all the a/f screws were 4 out. normally they differ from carb to carb from what I've seen. see if you can't give em a sync to give you a starting point.

However, The most common thing for popping in the exhaust is excess air. It 's either too lean or there is an air leak in the exhaust somewhere. The pops are when fuel left over from poor burns ignites.

Have a look see at your boots, fittings and exhaust fittings. See if something has come loose and is introducing more air. We all know how the Vmax's carbs hates air leaks.

From there I'd check the boots and plug wires. I'm still thinking atomization issues. easy and cheap to check, before ignition pieces are bought.

Hopefully Sean, Mark, Fargo or someone with a little more exp. will see this and jump on in and help with some suggestions.

After reading all this I dont see anything that is being missed.
When my bike is running like **** one of the easiest things to do is to check the sync. Most of the time that clears it up right away.
I cant explain the 1k-3k idle increase unless one of the chokes is not fully seating when taken off, could be sticking open.

One thing to check to make sure it is fuel and not ignition is to run all the A/F screws down, one at a time, and the bike should stumble. If the bike doesnt stumble/change idle when one of them is run down then you know which cylinder to start on.
Once you find the suspect cylinder, pull the plug, stick it back in the boot, ground it to the engine and fire it up to verify spark. If you have spark
more than likely your pilot circuit is clogged and needs a good cleaning.

Try one thing at a time
1. Sync- Doesnt fix move on
2. A/F screws all the way in. Listen for stumble. Btw if it does stumble than that cylinder is fine on both ignition and fuel. Make sense???
3. Pull plug, check spark. Good spark move to next
4. Clean the **** out of your carbs.

If this doesnt help then get back to us.

 

[vince95]

Thanks for all the tips! I will be working on the bike again this weekend and will see if I can find anything out of the norm.

 

[RagingMain]

Hey Vince
One other thing I forgot to mention
If you are having an ignition miss it will show up while you are tying to sync.
What will happen is you will notice that cylinders Vacuum dropping off quite frequently.
Dont ask me how I know this :bang head:
Cheers
Any questions PM me and I will shoot you my number

 

[Rick52]

If the TCI is bad, will you lose spark to the plugs?

 

[KJShover]

If the TCI is bad, will you lose spark to the plugs?

Yup, same as your pick-up coils. I'd check them first before putting some big coin on a new ignition. Fortunately your 2000 is new enough that Dyna still makes one for it.

 

[vince95]

Just an update on my 1995 Vmax:

I have had it in the shop for a couple months after trying everyones's suggestions and trying everything I could myself.

Mechanic noticed when he came to pickup the bike the left front exhaust pipe was warm while the other exhaust pipes were hot. Showed that the left front cylinder was not firing properly if at all.

Carbs's have been thoughly cleaned 5 times now (twice myself) - My mechanic cleaned them ultrasonically and completely disassembled and reassembled. Carbs are basically new too (came off a 2005 vmax when new and bike was used for the track and carbs drained and stored) All parts in carbs look clean and like new. He Synced multiple times and everytime they were dead on. A/F mixture checked and adjusted and spark is strong on all cylinders. He cleaned the carbs a couple times before the front cyclinder fired properly - must have been something stuck in one of the passageways.

Bike now does not have the high idle problem anymore and all exhausts feel hot to the touch. So it seems to be firing properly now.

But it still has the pop only out of the left rear cyclinder. Bike takes a few minutes to warm up and run without choke. Guess this is normal on most vmaxs. Took it out for a spin but still seems to run a little rough with the pop but alot better than before. Only notice the pop at lower speeds in 1st & 2nd. Seems to accelerate pretty good.

Again this problem started last September. It ran fine before and all of a sudden developed the problem of the popping sound, random high idle and running like crap (probably because of firing on 3 cyclinders). Well at least its running on all cylinders now & idle seems normal after warmup. When putting my hand over the exhaust you can feel the difference of air flow when it pops. Don't know what else to try for the popping issue. :bang head:

 

[COP RUNNER]

I WOULD START RUNNING " SEA FOAM " IN THE GAS , MY 2006 , I BOUGHT NEW AS A LEFT OVER IN 2007 , THE CARBS WERE ALL GUMMED UP FROM SITTING ON THE SHOWROOM FLOOR WITH GAS IN IT ! .. HAD IT BACK TO THE DEALER TWICE , FIRST TIME AFTER 76 MILES ON A FLATBED :bang head: , AFTER THE SECOND TIME , BIKE RAN A LOT BETTER , BUT RAN AS YOUR DESCRIBING YOURS TO RUN NOW ! .. VERY EARLY INTO THE FIRST TANK OF " SEA FOAM " , ( I PUT 9 OZ. IN THE FIRST TIME ) BIKE STARTED RUNNING GREAT , NOW I RUN IT IN THE GAS ALL THE TIME ! .. JUST AN OUNCE OR TWO PER TANK ! ... ***** LIKE MAGIC ! .. unk:

 

[COP RUNNER]

HERES SOME THINGS ABOUT " SEA FOAM " http://www.vmaxforum.net/showthread.php?t=10467&highlight=FOAM ALSO CLICK ONTO THE SEARCH SECTION OF THIS FORUM & ENTER SEA FOAM , THERES HUNDREDS & HUNDREDS OF STORIES ABOUT IT ! ... THAT TO ME IS YOUR NEXT STEP ! PUT 9 - 12 ONCES IN IT , AFTER LIKE HALF A TANK , OVER THE COARSE OF A COUPLE OF DAYS , THIS WAY WHEN IT SITS OVER NIGHT , ITS CLEANING & LOOSENING ANY **** IN THE FUEL SYSTEM & FOR THE LAST HALF A TANK , RIDE IT LIKE YOU STOLE IT & SEE WHAT HAPPENS ! ..