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Discussion Starter #1
Today toward the end of a successful 150 mile ride I was cruising at about 35mph in 4th gear. came up to a stop sign and pulled in the clutch to downshift and the RPM's stayed where they were at, about 3000 rpms. I came to a complete stop and tried twisting the throttle to slow it up. No dice. Idle stayed high.
Started up at the stop sign and the bike seemed sluggish but managed to get up speed. At about 30mph I pulled the clutch in and the idle was still high. Rev'd the engine. It responded normally but idled back to about 2500 rpms.
Turned engine off and restarted it. Idle to 2000 rpms for a few seconds then down to normal operating speed (1250-1300rpms)

Next stop sign Bike OK. Further down the road high idle again.
I checked the coolant and oil temp gauges and they were about 190-200 range. This is normal.

Bike continued to malfunction intermittently like this (high idle and sluggish response) until I go to pull into my development. Pull the clutch in to make a left turn and the engine quits immediately. I coast around the turn then hit the start switch. Engine starts immediately. I proceed home.

Checked DTC's. There are none.

In addition to these symptoms, occasionally it refuses to start on the first try (hot or Cold). It grinds away until I stop trying to start it then try again. It always starts on the second try. This may or may not be a symptom of the same or different problem but whatever.

Tomorrow, I intend to check the mechanical linkages to the throttle body and the IAC looking for binds or crud or anything that could cause sticking. Also the IAT for crud.

The sluggish start from the stop sign seems to indicate a to rich fuel mixture. What would cause the ECM to do this? What else should I look for? Anyone know where the engine temp sensor is?

I do have a PCIII on the bike but no changes have been made anywhere for the last 2-3,000 miles or so.
 

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I would do the same as you are doing but also take the PCIII out of circuit and do it in steps to rule components out as you go so you don't have to back track.Also look for vacuum leaks with an unlit hand held propane torch.Not having a code could me PCIII or vac leak and did the throttle resistance feel normal. Im no expert on this bike.Good luck with it
 

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Possibly an air intake or exhaust leak. Check that first.

These are symptoms common with auto-tuners and leaks. The PCIII is not a classic auto-tune but what happens is the fuel management keeps adjusting and readjusting itself. Ambient temps, engine heat, ect will cause more changes yet and it could be running out of adjustment in certain situations and/or temps.
 

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20 Eyes in my Head
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Does your PowerCommander have the throttle position adjustment? I think the older one I had on the old Rod did and you had to calibrate it once in awhile for this reason. Hook it up to the your computer and start up the bike and see what the TP is reading at 0% throttle while idling. I would start there as mine did that too and that was the problem....I believe I had the PCIII USB....but went to a SERT shortly thereafter.
 

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Killer Service Inc.
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When was the last time you lubed the cables and checked them?

When was the last time you lubed the linkage?

this is where I would start!!
 

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drag racer
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like rod said, i'd lube the cables and clean and put a drop of cable lube on the spring/lever on the throttle body first.
 

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Discussion Starter #8
I am going to inspect the mechanical aspects of this first. My cables are never lubed. I keep them cleaned out. The ferrules on the ends do get grease however. Never had a cable breakage problem.

The cables do not appear to be binding. I could twist the throttle and it would snap back as per usual. Will check for binds and twists etc.

Then on to vacuum leaks. Nice suggestion about the propane torch. I assume if I have vacuum leaks then the engine will surge as it sucks in the propane.

I can run without the PCIII. I will check the throttle position sensing piece of the PCIII. Bike runs a little rich without the PCIII but no damage to the engine will result. This I will do if the symptoms get worse.

The machine does not have a throttle lock. I discarded it when I installed my true cruise control.

I have not had the top end of the bike apart recently so something may have loosened up.

Thanks for all the suggestions guys. Gives me something to do next week.
 

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George
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I had similar sx once and it traced back to the IAT. Mine DID throw a code, but only once, although the malfunction continued... Re-seated the connector and been good since HYMMV.
 

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Killer Service Inc.
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clean the connector woud be a good thing also.

I agree with Cap

http://www.drislide.com/

This is what we use, shake up real well. push long needle down the cable and hold for 5 second.
This stuff really works.

Do not put to much in or you will have it all over.
 

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Discussion Starter #11
I had similar sx once and it traced back to the IAT. Mine DID throw a code, but only once, although the malfunction continued... Re-seated the connector and been good since HYMMV.
clean the connector woud be a good thing also.

I agree with Cap
Never did like that thing. Will look closely at it.
 

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Discussion Starter #13
john if you need a new one i have a brand new somewhere in the garage.
Thanks Luigi. Will keep it in mind. Haven't had a chance to look at it yet. Maybe Tuesdays project.
 

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I am having problems with stalling at idling/ unable to fire without throttling and in my search for solutions it seems according to FAQs on the power commander website that if power commander has any damage to wiring harness or there any shorts then the bike will start acting very weird with symptoms such as overly rich running, hesitation, stalling, running rough as if cylinder misfiring, etc.... and that according to them can suddenly appear after yrs of running fine! So I would remove the pc111 and see if the problem goes away and then if it does either find problem or simply switch to HD race tuner.
 

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Discussion Starter #15
Problem resolved. Nothing more than a junked up throttle cable. I pulled the air box and watched the linkage on the throttle body. When I opened the throttle and released it did not pull back. Removed the throttle cable from the linkage and manually operated the linkage it sprung back like it should.
Lots of brake cleaning fluid and some spray Silicone and things are back to normal.
Thanks for the assistance and moral support guys.
 

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Killer Service Inc.
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Great Job!!!

Glad you got it fixed.
 

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Discussion Starter #17
Well I lied. The problem is not resolved. Cables are now free but long ride (80 miles) came to a traffic light no problem. Went another mile and another traffic light. No problem. Went another 1/2 mile and when I released the throttle the engine kept a high idle. Tried twisting the throttle, No luck. Stopped at a convenience store and verified the throttle was indeed closed. Went in and had a soda and some munches. Came back out and started the bike. Seemed better but still not normal.
Then I removed the Power commander and tried again.
Hit start switch and bike started with a high idle but after about 10 seconds settled in to a normal idle. Been that way since. I have run through two tanks of gas ( 250-300 miles) with no problems. I can run w/o the PCIII without fear of running too lean so I will leave it this way for a couple of weeks or so and see what happens.
 

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20 Eyes in my Head
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Well I lied. The problem is not resolved. Cables are now free but long ride (80 miles) came to a traffic light no problem. Went another mile and another traffic light. No problem. Went another 1/2 mile and when I released the throttle the engine kept a high idle. Tried twisting the throttle, No luck. Stopped at a convenience store and verified the throttle was indeed closed. Went in and had a soda and some munches. Came back out and started the bike. Seemed better but still not normal.
Then I removed the Power commander and tried again.
Hit start switch and bike started with a high idle but after about 10 seconds settled in to a normal idle. Been that way since. I have run through two tanks of gas ( 250-300 miles) with no problems. I can run w/o the PCIII without fear of running too lean so I will leave it this way for a couple of weeks or so and see what happens.
I said it earlier in the thread, check the tps setting with the Dynojet software so the PC is reading throttle position correctly. Had this same issue years ago when I had a PCUSB on my old 2003 VRSCA. Instant fix. It's free and easy to do...and might work for you. ;)
 

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Discussion Starter #19
I said it earlier in the thread, check the tps setting with the Dynojet software so the PC is reading throttle position correctly. Had this same issue years ago when I had a PCUSB on my old 2003 VRSCA. Instant fix. It's free and easy to do...and might work for you. ;)
Thanks for the reminder but I think I will ride without it for a few hundred miles to see what happens. If no failures I will re-install it and check out the TPS as you suggest.
 

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You need to doa search on IAC motors.
First, if the Throttle (TPS) is above a value, either due to real sticking throttle, or incorrect TPS 0% setting, the IAC motor cannot control the idle air rate.
Also, when you key off, the IAC should "reset."
That is it adds "counts" and then drives itself into the seat and then backs out a calibrated number of steps! That is the4 ONLY way an IAC systems "knows" location.

IAC motors are notoriously BAD at "losing counts" during an ignition cycle. Some IAC Motors can be cleaned, but many need to be replaced once they start losing counts. ( IT is a metal screw "pintle" in a nylon body. The nylon wears over time and the IAC systems fails to function properly.
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For those so interested, a count is a rotational movement of the MOTOR related to electrical windings in the actual motor. When the IAC "wears" the pintel can vibrate enough to "register" a count of movement, even when the actual pintel position did not change. Over a little time running down the road those "lost counts" add up and the software " position" no longer equals actual position. Sometimes if the "counts" are close enough, the system will come back into control. If enough counts are lost, the software cannot add or subtract enough counts to be in control!! Yet the motor will "resest" at key off and appear OK, for a some amount of run time.
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All that said, cold start A/F ratio is also dependant on proper IDLE air rate. Some of the idle air is the st screw on the throttle bodle (blade position, and that is why you should not try and "adjust" a set screw on the throttle body!!!!)
The "other" part of idle air rate at start up, is the IAC motor "parks" at a set position, but can be in the wrong position, with a bad IAC motor!!!

IAC motor "housing clearances" can also become dirty and can be cleaned with "carb cleaner."
(If you clean the IAC housing, you might also wipe out the throttle bore too!!)
Just a couple of random thoughts from a guy that fought IAC motors most of my career!!!
 
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