Troubleshooting Help! Bike runs like sh#t!!

[fireman68]

2003 Nomad, chucksters single air intake K&N filter with tunnel removed, coaster plates with meddesa removed, Vance &Hines dual baggers and TFI.

I have been battling mechanical problems for about 2 months now and getting frustrated. It all started with suddenly getting bad gas mileage in town. Reset TFI and was running fine. Then I started having issues with bike not wanting to stay running randomly at first start up. Sometimes It would start right up and after a few minute warm up, when I would take off it would cut out, sputter and barely run. Other times it ran fine. My first thought was battery since it was getting old. I had it checked and it was bad. Installed new battery from battery mart. I still had issues with it running. My next thought was possibly bad gas since there was a recall on some gas that was delivered in my area. I drained that gas and put in fresh with some sea foam in it a couple of weeks ago and it seemed to run fine. Today is the first time I had a chance to ride it since then and the same thing. It started fine. Idled fine while warming up for about 3-4 minutes then when I took off it started cutting out, sputtering and backfiring through the throttle body. I got it pulled over to the side of the road and it died a couple of more times. I got it to stay running after about 5 minutes and once it warmed up completely (it was about 65 degrees out) it seemed to run fine. I then rode for about 30 miles and it was fine.

Obviously I'm not the most knowledgable when it comes to mechanics and I am merely guessing, but I like to try and figure things out before I completely give in and take it to a mechanic. Any suggestions on what I can check and how before I give up would be appreciated.

[old curmudgeon]

You've got an identical set up to mine, although I have a 2006. I had some problems with rough running as well but usually not until the bike had warmed up. I can only suggest what others on this site suggested while I was working through my problems. But numero uno, as lame as it sounds, make sure all your plug wires are pressed firmly down on the plugs. I found one that felt tight but wasn't actually snapped on to the plug. Fixed all my problems. From there:

• Make sure all the vacuum lines have been completely and permanently plugged. Pay particular attention to the vacuum tubes that used to go to the cold idle solenoids
• Check all the connections. Some have found loose coil wires. I found a loose ground wire. Especially check the ground connection coming off the battery at its terminal end.
• Clean the throttle body
• Make sure the vent tubes for the fuel tank are not crimped anywhere. I re-routed mine but I'm not sure if it helped my problem...
• I'm sure others will have more suggestions

Best of luck! These things can be a real bugger...

[ringadingh]

Do all the above, especially make sure the throttle body has been cleaned. Use a old toothbrush and carb cleaner, scrub well around the butterflies. Try new spark plugs also.

[waterman]

Originally Posted by ringadingh

Do all the above, especially make sure the throttle body has been cleaned. Use a old toothbrush and carb cleaner, scrub well around the butterflies. Try new spark plugs also.

Another one on cleaning the throttle body, After cleaning with a toothbrush, start the engine, rev the engine and start spraying cleaner into the throttle body. You will have to do quick sprays, pause for a second and repeat. I do that at least once a year.

[cnc]

Also, just to be clear when you suspected bad gas did you take the tank off, turn it upside down and shake the last bit out? Just removing the fuel line and draining will leave behind quite a bit in the bottom of the tank. Water being heavier than gas it will sit at the bottom. When I had bad gas it caused similar symptoms after riding a bit or filling up as either would cause the water at the bottom to mix with the gas and pass through the system.

Another thought, can you unplug your TFI?, because there was a fellow on here who was going through the same symtoms and found that his fuel processor was screwed up.

[Blueraven]

In my experiences with fuel processors, remove them from the mix so that you can rule it out being the problem. I had the same problem with my FP and it was BAD. Do for your PIECE of MIND.....

[Blueraven]

Originally Posted by cnc

Another thought, can you unplug your TFI?, because there was a fellow on here who was going through the same symtoms and found that his fuel processor was screwed up.

Are you refering to me...... LOL!

[cnc]

Originally Posted by Blueraven

Are you refering to me...... LOL!

Yes I was Rhys, As I remember you were about to pull your hair out looking for the fix.

[fireman68]

Ok. I wanted to make sure I only tried 1 thing at a time to make sure I pinpoint the problem.I started with unplugging the TFI today. Bike started up ok, but didn't want to idle. Then once I adjusted the idle knob it ran well (I remembered that I had it turned down some when I set up the TFI). I took it for a short ride and the bike seemed to run great. It seems right now that the TFI is the problem, which sucks because it is only a couple of years old.

My next question, How much can I ride with my set up and the TFI unplugged before I need to be concerned about damage from running too lean? Am I ok if I just watch for engine ping? (on my initial ride, no ping at all, but got cut short because of a storm). I want to make sure that is the problem before I drop another $200. I also checked all my vacuum caps I installed from removing the medussa" hoses and electrical connections while I had the tank off and everything was ok.


Thanks.

[VulcanE]

Just keep an ear to your engine, and with the temperatures cooling down, ping will be less likely. I would give Dobeck a call, 'cause they used to warranty the TFI for a long time.

http://dobeckperformance.com/

[macmac]

Bad TFI? So far I only know of the 1....n Seen a few bad PC III's......

I am curious about the TFI setting you had and then made the change because of poor running.

I am more concerned about vacuum leaks you may still have.

At the point you are now i would ride the bike easy because it will be overly lean.

You need to see if the engine is going to be consistent now. If it is then the TFI is the blame. If not maybe the TFI is ok and you have a vac leak.

You can pull the plugs and see if they are white, tan and or black. Don't expect to find black with no TFI and or a vac leak. White to blistered white is lean.

You could buy a old fashion propane torch as adding fuel and with no flame of course point the torch at the intake with no air filter and the engine running at idle.

Too much extra fuel and the engine will drop RPM and sort of chug..

If there IS a vac leak the RPM will go up ,maybe sky high as the added fuel meets or tries to meet a air leak.

A just right mix will show as a drop in RPM quickly and as soon as the added fuel is removed the rpm will recover.

Besides the caps and the one port on the throttle body there are other places a vac leak can be....

But start with what you did, then check the back of the capped off ports to the now missing ISC's because these steel lines turn to rubber, then steel again and rubber again before they enter the intake manifold.

Check the brassw port on the throttle body for loose, cracked or missing caps/hose because if there is a single back fire thru the T body any and all of these caps can be blown off or blown loose and maybe just cracked.

You must have a 100% air tight seal.

If that is all good, then still the O rings could be bad that act like intake manifold gaskets. To see use the torch pointing there as best you can.

Also there is throttle plate shaft seals.... never hear of a bad one yet, but that won't last for ever, as sooner or later one is going to fail and who knows you could be the first on your block!

My 01 and my 06 were set up this way to other than I run a right side Cadman. OEM backing plate sealed off and a Spector air filter and cover.

No technical difference what so ever.

[fireman68]

Mac,
I have been battling the settings on the TFI for a while. Most noticeable problem early was poor fuel mileage in town. After some help from you on an earlier post, I reset the TFI by adjusting pot 1 at idle. Setting pot 1 I only would get an increase in idle of about 50-100 rpm so I set it at that peak (2:30). Pot 2 I set on feel.It was about 3. It seemed to run well for a few short rides. Then I started having the bigger issues, until warm up mostly, that I described in this post. I had already tried running the propane torch around the throttle bodies and engine with no effect. I did not try it directly into the intake though. When I removed the air tube previously, the vacuum lines (both metal and rubber parts) that went to the ICS were traced back to the throttle body and removed and capped off there. I checked all those caps and they are snug. They are not glued or clamped on, so I don't know if that makes a difference.

I haven't had much of a chance to ride since disconnecting the TFI since it has been raining for the last 3 days, but the first ride was good. I have emailed Dobeck to see if I can send it in and get it checked, but have not heard back if that is possible yet.

It's been a frustrating summer. Due to a busy schedule with kids this year, I haven't had many opportunities to ride, and when I did have a chance I spent most of that time troubleshooting. I appreciate all the help.

[macmac]

Fireman I hear that. been busy here too and other BS is messin up my riding time.

Sorry I repeat stuff, but trying to help as i do, I just can't recall who, no faces not many real names old fart that i am, CRS Strikes ya know.....

I think you have a vac leak... Add extra fuel right into the T body.

Bad MPGS and white plugs is sure to be a vac leak and it may be in just one cly.....

So far we don't know about any white plugs.

If you think the TFI is bad or the ECU is screwy and you have too much fuel which I really really doubt, pop off one of those caps and let it have a big vac leak. If that extra un-metered air gets RPM up to meet air to fuel mix it will be some exotic so be ready for a total run away engine and to be able to shut it off.

Yanking the whole intake off is a pain but it is doable.

When adding extra fuel and I used to use WD-40 but in the past few years it doesn't seem to work like it did....

But any way addi9ng extra fuel just has to do something...... If mix is right the engine should lug down and clear when the fuel is removed or taken away.

If there is a vac leak then the fuel will attempt to meet the correct ration and RPM has to go up.....

You can do this on a engine that seems to be running well just to check mix too. But right into the t body hard....

[KURT44]

MY 05 1500 CLASSIC started to run bad wich included backfiring. Ended up being the connection from the brain box. If you still have problems, maybe try this, my mechanic just cleaned and greased the terminals.
good luck!

[fireman68]

Finally have a nice day and a little time to do some troubleshooting. I still have the TFI unhooked. I used the propane torch again. I ran it all around the throttle body and engine. No change to the RPMs. I pointed it directly in the intake with filter removed and RPM dropped some and chugged a little, but not a lot until I removed it. The butterfly's are nearly closed at idle though. As of right now it still seems to be running ok without the TFI. Before I disconnected the TFI my plugs had dry carbon build up on them. They were all the same so there wasn't a cylinder worse than the other.

Update:
After I did some investigating with the torch, with the above results, I went to go for a test ride and the same old thing again, engine kept dieing, cutting out, sputtering and not wanting to run. Fought to get it back in my garage and had to use a little of the high idle now to keep it running and ran the torch again. This time when I stuck it in the intake with the filter off, the idle sped up a little. Nothing when sticking it around the engine and throttle and no change.
Is it possible to have an occasional vacuum leak ? What would be different one time from the next? I don't have a lot of hair, but I am about to pull what I have out!! No clue where to go next.