A big throttle problem
Thread Starter
|
2nd Gear
Joined: Aug 2013
Posts: 6
Likes: 0
From: Winchester Va
A big throttle problem
I have a retired cop bike and I am having some significant problems with it. When I roll the throttle back it stutters and wants to shut off. It feels and sounds like it is starving for gas. It has progressed from only happening once in a while to now every time I ride. Some other symptoms are extreme fuel mileage loss, I went from @ 40mpg to below 30mpg, there is a severe low RPM hesitation to the point that it stalls, and then does not want to start. If I let it sit for a half hour or so it will restart but it continues to hesitate and stall at low throttle and low rpm. Pretty significant smell of gas fumes also.
It cost me a pretty hefty tow bill and made me late for work two weeks ago. I have only had the bike for 4 months and have put 3000 miles on it with no issues until this.
So far I have checked the following with DVOM:
plug wires
coil
engine temp sensor all within normal limits as per both the manual and the forums
checked for exhaust leaks and found none
replaced oil pressure temp sensor (due to oil light flickering 1500 miles ago)
replaced crank position sensor to attempt to fix this problem (no luck)
cleaned throttle body and IAC valve including the connections
checked all connections to all sensors I could find
gas cap and vent appear to be clear
no blown fuses
I have replaced spark plugs which were gaped wrong, and it ran like it should for 25 miles and then the problem returned.
One plug was sooty (rich) and the other wasnt as bad but had obvious signs of incorrect gap
It is running rich and when acting up it shoots an impressive blue flame
The engine light is on and off but when I attempt to pull the code with the process described in the forum it just blinks once as if it is only a historic code.
I haven't added any mods and I have the stock air intake
I searched the forums and can't find an answer. Hopefully someone can point me in the right direction.
Thank you in advance
It cost me a pretty hefty tow bill and made me late for work two weeks ago. I have only had the bike for 4 months and have put 3000 miles on it with no issues until this.
So far I have checked the following with DVOM:
plug wires
coil
engine temp sensor all within normal limits as per both the manual and the forums
checked for exhaust leaks and found none
replaced oil pressure temp sensor (due to oil light flickering 1500 miles ago)
replaced crank position sensor to attempt to fix this problem (no luck)
cleaned throttle body and IAC valve including the connections
checked all connections to all sensors I could find
gas cap and vent appear to be clear
no blown fuses
I have replaced spark plugs which were gaped wrong, and it ran like it should for 25 miles and then the problem returned.
One plug was sooty (rich) and the other wasnt as bad but had obvious signs of incorrect gap
It is running rich and when acting up it shoots an impressive blue flame
The engine light is on and off but when I attempt to pull the code with the process described in the forum it just blinks once as if it is only a historic code.
I haven't added any mods and I have the stock air intake
I searched the forums and can't find an answer. Hopefully someone can point me in the right direction.
Thank you in advance
Thread Starter
|
2nd Gear
Joined: Aug 2013
Posts: 6
Likes: 0
From: Winchester Va
I did check for codes using the process described in the forums, however instead of blinking out the code sequence it just blinks once, I found somewhere that it typically means a historic code which cannot be read without a scanner, which I don't have (yet). I have not checked the fuel delivery system and I think that is the way I am going to proceed next. I am going to test the TPS now and then ill look up how to check the voltage regulator with a DVOM and ill report my findings. Thanks for your replies.
Outstanding HDF Member
Joined: May 2008
Posts: 2,543
Likes: 19
From: Ashland Ohio
Take some needle nose and reach in and see if you can wiggle the throttle plates inside. Besides sounding like starving for gas... it can be getting too much air. If the throttle shaft is loose, its most likely leaking air around the shaft.
Thread Starter
|
2nd Gear
Joined: Aug 2013
Posts: 6
Likes: 0
From: Winchester Va
Ok so here is the latest update, I tested the TPS and stared with values around 1.7 at idle, as I increase the throttle the value increases to 2.5 and then decreases until I reach full throttle at around 1.1. I replaced the TPS and the values now start at 2.1 ohms increase to 2.25 as I begin to open the throttle and then decrease to 1.4 at WOT. This is a brand new sensor and it has me stumped. It is the same activity as the TPS I just removed but with different values. It is a smooth with no spikes or extreme changes. While doing this I also noticed a vacuum plug at the throttle body (thought to have to do with the cali. emissions portion) dry rotted. I replaced that also. I just readjusted the throttle and idle cable. I did attempt to wiggle the throttle plate, it is nice and tight and appears to make good contact at idle position. Also just replaced the plugs again. I cleaned and re checked the gap on the ones I took out.
Trending Topics
Road Master
Joined: Jul 2007
Posts: 1,009
Likes: 4
Pin hole in internal fuel line. Replace the main 30 amp circuit breaker with a 40 amp breaker.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Thread Starter
|
2nd Gear
Joined: Aug 2013
Posts: 6
Likes: 0
From: Winchester Va
Im draining the tank as I type this. I'm going to check the wires running to the fuel injectors, I have read breakage is a common problem. While I have the tank off I'm going o replace the filter and lines inside the tank. Ill repost my findings.