Loping idle

[Tenman]

Gen 1. Got a rough idle with some slight backfire. Runs fine above 2k rpm. I checked plugs, coils, vacuum leaks, synced TB and put n new gas. No Change. Gonna remove the injectors and clean them. I have 3 dealerships that are each about 100 miles away. Been ripped off by 2 of them. When I removed my air box. The valve cover hose has not been on it since I had the valves checked 1k miles ago. Ugh. The last dealership within 100 miles gets 2 star reviews. I hope this link works. I’m open for ideas. https://share.icloud.com/photos/0d19bRkDwPt3-meXCzxMseEDw

 

[cyclemike4]

Gen 1. Got a rough idle with some slight backfire. Runs fine above 2k rpm. I checked plugs, coils, vacuum leaks, synced TB and put n new gas. No Change. Gonna remove the injectors and clean them. I have 3 dealerships that are each about 100 miles away. Been ripped off by 2 of them. When I removed my air box. The valve cover hose has not been on it since I had the valves checked 1k miles ago. Ugh. The last dealership within 100 miles gets 2 star reviews. I hope this link works. I’m open for ideas. https://share.icloud.com/photos/0d19bRkDwPt3-meXCzxMseEDw

I have no idea what could be causing this issue but I would be interested in what you find. My bike gets like that and at times it is worse than others. As you have done I go over it with a fine tooth comb. Nothing significant is found. What seems to help mine out some what is find good gas and run it hard down the interstate for a couple hundred miles. It may or may not really help it but it always feels better after that. Usually when I get back from a big road trip is when it runs its very best. May have something to do with it not sure.

 

[Sierra1]

The closest mine gets to this is on those days when it's not warm, but not cold. Like the ECU is trying to decide how much fuel/air to mix.

 

[Jlq1969]

Gen 1. Got a rough idle with some slight backfire. Runs fine above 2k rpm. I checked plugs, coils, vacuum leaks, synced TB and put n new gas. No Change. Gonna remove the injectors and clean them. I have 3 dealerships that are each about 100 miles away. Been ripped off by 2 of them. When I removed my air box. The valve cover hose has not been on it since I had the valves checked 1k miles ago. Ugh. The last dealership within 100 miles gets 2 star reviews. I hope this link works. I’m open for ideas. https://share.icloud.com/photos/0d19bRkDwPt3-meXCzxMseEDw

Check that the coil connectors are good (or ohms)… If you want, you can test the coils working (the problem is that it will give you an error that you will have to erase)... but a while ago, when I installed a Qshifter, I forgot to connect 1 of the 2 coils of a cylinder... the check light turned on, but the first thing I noticed was that the idle was unstable, it accelerated and it was corrected, but when it returned to the idle rpm, it was unstable….

 

[audiowize]

Mileage? Cam chain tensioner status? Slipping a tooth can give some weird operating conditions like these.

 

[Chav]

Mileage? Cam chain tensioner status? Slipping a tooth can give some weird operating conditions like these.

Don't say that haha. Mine has 2k miles and it looks as well I've noticed. I'd be heart broken if it had a cam chain issue already.

 

[Boris]

Fuel pump filter? Or does the above 2k rpm rule that out?

 

[Tenman]

I had a new fuel pump put in 1k miles ago @ 70k miles. Replaced the cct.

 

[audiowize]

How are your valve clearances?

 

[~TABASCO~]

Miles?
Valve service ?
Clean air filter ?
Do you ever use any sea-foam ?
Fresh plugs ?

 

[Tenman]

Miles?
Valve service ?
Clean air filter ?
Do you ever use any sea-foam ?
Fresh plugs ?

71 k miles. Valves checked at 24k and 70k miles with plug change. Air filter good. I use Techron often. It did the same thing a few hundred miles ago. I checked TB sync. Wasn’t off much. While I had it apart. I pulled the plugs and grounded them to check spark. Put it back together and it was healed. Loping is back now. I’ve had vacuum caps crack that sounded a lot like this. If u were closer. It would be there. I also gave it an Italian tune up

 

[Boris]

Tank vent hoses blocked/kinked?

 

[Tenman]

Nope. If I can find a road that I can do an xtended Italian tune up on. I’m gonna skin it back. So far I’ve just ran it up to 110 mph a few times and had to back off. Hard to find one around here. Deer, shoulders grown up over head high and cops everywhere when u don’t need one.

 

[audiowize]

Good extra info, that's helpful. The next thing I would recommend is using an IR thermometer to check each header pipe exit while warming up at idle. If you're only running on one, this will become rapidly apparent with an IR gun. If that ends up being the case, it's not usually too difficult to track down what isn't working properly.

 

[MattR]

The closest mine gets to this is on those days when it's not warm, but not cold. Like the ECU is trying to decide how much fuel/air to mix.

A good ecu flash will cure that


Sent from my iPhone using Tapatalk

 

[Sierra1]

There's only a few days a year that the ECU has that temperature decision, and it's only at idle. Once rolling, all is normal.

 

[Tenman]

It's missing above 2k rpm in neutral too. Can't tell it going down the road. Shot the headers with my temp gun. Theyre both withing 20-40 degrees of each other depending on where you point it. It sure does sound like a plug is misfiring. They don't have a 1k miles on them. Might just change them out in desperation. I looked at some connectors. Clean as new. I've never seen a error code on mine. Seems like I should have something show. IDK Frustration setting in. As I have said before. If you have a good local mechanic. Count your blessings

 

[Tenman]

Changed the plugs that had 1k miles on em and shot some carb cleaner in. It still ran a little ruff down low. After a tank of gas. It’s running fine again. I found the valve cover hose to the air box had been off since that chicken $hit stealership allegedly checked my valves. Check out the reviews on G. N. Gonzales n Baton Rouge La

 

[5fl]

Hello,i have just solved my random stalling/low idling issue by pure luck,ive been chasing the problem for a while now and thought i would have another look at my fuel pump , tank up and disconnecting the fuel hose from the fi rail,small amount of fuel came out from rail as normal but something caught my eye in the steel pipe,a small piece of black plastic was in the pipe!!! Fished it out with a bit of wire,rectangle about 3mm x 6mm .hmmmm
Looked at the fuel hose,it has three small plastic guide tabs to help locate it on the rail,one of mine was missing,somehow when previouly connecting i have broken a tab off inside the fuel pipe!!!
If you have idling/ fuelling issues its pretty easy to check the fuel hose still has the three tabs,if it hasnt got the three tabs i know where one might be!!

 

[rodeoclone]

Changed the plugs that had 1k miles on em and shot some carb cleaner in. It still ran a little ruff down low. After a tank of gas. It’s running fine again. I found the valve cover hose to the air box had been off since that chicken $hit stealership allegedly checked my valves. Check out the reviews on G. N. Gonzales n Baton Rouge La

My 2015 w 50k is acting exactly the same Tenman. Rough idle up to 2500 rpm. I’ll try new plugs and fuel system cleaner. Hopefully not a coil. I’ve checked the coil resistance before and recall that it wasn’t exactly as the book said nor uniform across coils. The idle was fine back then also, so I didn’t fret.