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Discussion Starter #1
Hello,

At the beginning I'm sorry for my english :)
I have VRSCA 2002, a week ago after the ride my v-rod on idel have above 2000 RPM and lights up chceck egine.
I check a code and: P0505
I read a little bit and I bought a new one IAC install, start a bike and everything was fine, but when I made a small round and the engine warmed up, it's exactly the same again.
Where to look for the problem now ?

Thank you for all the advice

Krystian
 

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Hello,

At the beginning I'm sorry for my english :)
I have VRSCA 2002, a week ago after the ride my v-rod on idel have above 2000 RPM and lights up chceck egine.
I check a code and: P0505
I read a little bit and I bought a new one IAC install, start a bike and everything was fine, but when I made a small round and the engine warmed up, it's exactly the same again.
Where to look for the problem now ?

Thank you for all the advice

Krystian
Could be a throttle cable issue with not returning or possibly the engine temp sensor. Does it smell like it's running too rich at high idle when hot?
Ron
 

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Discussion Starter #3
When engine is cold everything is ok 1400-1500 RPM.
I start riding, and after a few minutes I don't need use throttle...
stop, the engine cools down and everything returns to normal.

where is engine temp sensor ?
 

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On the t
When engine is cold everything is ok 1400-1500 RPM.
I start riding, and after a few minutes I don't need use throttle...
stop, the engine cools down and everything returns to normal.

where is engine temp sensor ?
On the thermostat housing, seen from the left side of bike Generally if defective the fans won't operate either and engine will overheat. Do you have a power commander on this bike? It still could be IAC related.
Ron
 

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The Hawk
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On the 2002 v rods the intake air temperature sensor was placed down between the heads and is susceptible to engine heat. Harley made a change to relocate that sensor up to the air box and that fixed the issue. They make a pigtail extension to move the 2002 sensors to the air box, or you can make your own.


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Discussion Starter #6
On the t

On the thermostat housing, seen from the left side of bike Generally if defective the fans won't operate either and engine will overheat. Do you have a power commander on this bike? It still could be IAC related.
Ron
I do not have any power commander.
I'll try to warm up the motorcycle, and see if the fans turn on, today it is snowing in Poland, so it can be difficult ;)


On the 2002 v rods the intake air temperature sensor was placed down between the heads and is susceptible to engine heat. Harley made a change to relocate that sensor up to the air box and that fixed the issue. They make a pigtail extension to move the 2002 sensors to the air box, or you can make your own.
I have to read about it and try to do it myself
 

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On the 2002 v rods the intake air temperature sensor was placed down between the heads and is susceptible to engine heat. Harley made a change to relocate that sensor up to the air box and that fixed the issue. They make a pigtail extension to move the 2002 sensors to the air box, or you can make your own.


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True, but the IAT will only lean and richen mixture, not alter idle rpms.
Ron
 

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Discussion Starter #8
Ok, I warmed up the motorcycle and i know:
i dont need go to ride, after 2-3minuts Check Engine P0505 lights up.
And Fans starts when the motorcycle is hot enough

Video:

A new IAC need be programed ?
And i change sparkplugs few days ago ?
 

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Ok, I warmed up the motorcycle and i know:
i dont need go to ride, after 2-3minuts Check Engine P0505 lights up.
And Fans starts when the motorcycle is hot enough

Video:

A new IAC need be programed ?
And i change sparkplugs few days ago ?
No IAC reset needed as it sets itself on each key on event but it's pointing to loss of idle control. Do you have any air leaks in the intake system? An IAC has limited amount of range to contol air inlet. Any leak will overpower it's ability and the air leak adds extra air in which raises the idle rpm. Without some form of logging to see the steps the IAC is using, it's tough to identify what's going on. Your cold start 1400 ish , is about right so it must be working in that range. Check throttle body boots for cracks or loose and see if that rubber plug is on the rear throttle body. If it's missing it's an air leak there. The fact the fans come on shows the temp sensor is working and engine is not staying in cold start rpms. One down. Air leak checks next. Make sure your throttle is returning to full stop at the throttle bodies and well. If not, this extra air coming in will overpower what the IAC can pull back, so the idle will be too high.
Ron
 

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Discussion Starter #10
No IAC reset needed as it sets itself on each key on event but it's pointing to loss of idle control. Do you have any air leaks in the intake system? An IAC has limited amount of range to contol air inlet. Any leak will overpower it's ability and the air leak adds extra air in which raises the idle rpm. Without some form of logging to see the steps the IAC is using, it's tough to identify what's going on. Your cold start 1400 ish , is about right so it must be working in that range. Check throttle body boots for cracks or loose and see if that rubber plug is on the rear throttle body. If it's missing it's an air leak there. The fact the fans come on shows the temp sensor is working and engine is not staying in cold start rpms. One down. Air leak checks next. Make sure your throttle is returning to full stop at the throttle bodies and well. If not, this extra air coming in will overpower what the IAC can pull back, so the idle will be too high.
Ron
Everything looks normal, the best way do find air leaks ?

603596

603597
 

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Everything looks normal, the best way do find air leaks ?

View attachment 603596
View attachment 603597
A nozzle and brake cleaner in the green area of both. Did you alter the screw with red arrow? Everything seems to look ok but you can try this. Tape over both throttle bodies and start engine. Yes it will run this way and in a healthy system at idle there will be no noticeable difference in how it runs. This way, unless there is a leak at the boots, the engine will run strictly on the iac port. If the idle is normal both cold and hot when taped off, the blades are too far open for some reason. If the idle doesn't change to normal while taped off and no boot leaks, then the issue is still IAC or IAC wiring related. Do you hear the IAC make noise when you turn the key off. Turn key on and then off but don't start engine. Key on, the fuel pump will drown out the IAC noise so ignore that. You should hear a rubbing scrubbing sound for a second or two as soon as the igniton is turned off. Make sure handlebar switch is set to run when doing this. If you can't hear this sound, it might be a wiring issue to the IAC unit.
Ron
 

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Discussion Starter #12
I didn't change the screw (red arrow)
no hear any strange voice:

It seems to me that it has to do with temperature, the colder the motorcycle, the later the check engine lights up after reset
 

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I didn't change the screw (red arrow)
no hear any strange voice:

It seems to me that it has to do with temperature, the colder the motorcycle, the later the check engine lights up after reset
IAC seems to be functioning as it should. Without some form of logging data this is going to be hard to identify. Did you check for leaks and tape over the tb inlets to see if idle is normal? Yes the IAC is controlled via a temp table in the calibration. Cold, it lets more air in and as it heats up the IAC slowly closes to reduce inlet air and drop the rpm. If it's getting air from somewhere else the idle will be higher then normal and there won't be enough low steps in the IAC to control this to the specified rpm/temp and it will throw a code. The reason I asked if you monkeyed with that red arrow screw is if the TPS voltage is set too high, the ECM will have trouble identifying settings for idle via the IAC. All this shit is interconnected for a final result in the end. Logging , you can see what steps the IAC is running at at all temps as well as what the TPS volts are at 0% throttle. Trial and error can work on this but it can be frustrating until you find the culprit. For now, tape over the throttle bodies and compare both idle and see if the code re appears when hot. Leave the IAC port open as usual. I suspect no difference but worth ruling out. While taped over, shoot some brake cleaner gently around the boots and note any drop in engine rpm. The taping will help prevent false readings that otherwise would cause the brake cleaner to be sucked into the tb inlets.
Ron
 

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Ron-
Silly question.. but the tps is a 3 wire sensor, yes? 5 volt reference, signal and ground? If so, one could backprobe the signal wire and if there was a known good voltage, tps can be verified. (Usually around .5v I would guess). Also, does this bike use an o2 sensor? Here too, a voltmeter (labscope better still) on the signal wire would indicate if it’s running lean (less than 450mv) and be a clue to a possible vacuum leak.
603603
image.jpg
603604
image.jpg image.jpg image.jpg image.jpg
 

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You can probe the TPS from signal to ground. At idle or key on only it should read between .045 -.047 volt and twisting throttle to stop, about 4.6-4.8 volts. This will give you an idea the blade opening and tps setting good as a rule. O2 sensor probing, don't think that will work well for a leak test. What you could do is that rubber cap on the throttle body, it can be removed and a vacuum gauge hooked up. These engines generally idle at 24-30 kpa +/-2. I think most vac gauges this will be in the 22 range on the scale but do the pressure conversion anyway. The signal wire of the map sensor can also be probed but a pain in the ass to get to. You can probe the map sensor at the ECM , slightly less of a pain. Same with tps wire at ECM. If you probe it, again the engine should be in the 24-30 kpa range, in which the voltage on the probing should be at idle 0.75-1.00. A higher volt reading then that, say 1.5 or more would indicate a leak between the throttle plates and map sensor. Do you know anyone with a PV unit. It will plug into your bike and show all of these signals. Same with anyone with a TTS. While both of these marry to the owners bike when loading a cal, they don't need to be married to use the basic signal viewing functions. It would make your life so much easier if you can dig one up.
Ron
 

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Discussion Starter #18
Well, gentlemen, I found the reasons for the increased RPM and error P0505.
The problem is the nut that secures the filter cover...

603642


the harder I screw it, the RPM increases and an error lights up.
At this moment he is screwed, just to keep it. without resistance

But I'm not going to leave it like this, and now the question is, what does this stick with RPM have in common?
 

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Are you tightening it so much that it is managing to tweak the seal of the throttle bodies? Essentially creating a giant vacuum leak.
 

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Listening to the last video, cycling the IAC, it sounded odd, do you have access to another VROD to compare sounds during the last few seconds when it's resetting?

You can see the pintle is in the ready position for cold start, then after you shut off the ignition main switch, the pintle moves to fully closed then backs up to ready cold start.
 
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