Code 18

[Snake Ranch]

Yesterday after moving about 150 yards for the first time in the morning on a city street the red warning light started flashing and the dash display showed, CODE 18.

Every thing sounded good and ran good, so whats up this this?

I shut the engine down and then started it again, same thing, so I shut down a second time and waited a short time. When I fired the engine up all was good and it never came back.

I am surprised to find out my service manual doesn't have a listing for the fault codes. So the internet search revealed this code 18 indicates "ACCELERATOR POSITION SENSOR MALFUNCTION".

My question has any body been able to connect this code 18 to the problem where the engine will rev up by it's self after sitting when hot and not completely cooled down and not return to idle until IT gets ready to?

I have done the throttle body cleaning for the high idle problem but that didn't help.

I have a feeling this engine has been talking to me for some time but the dots have not been connected as of yet.

[Sabre-t]

There are a couple of possibilities that I can think of besides the throttle bodies.

Do you let the electronics reset for a few seconds between turning the key to "ON" and pressing the starter button? The electronics need to reset before you crank it. Even blipping the throttle too soon after cranking will mess it up. This is especially true on the older Voyagers/Vaqueros. The electronics boot up much faster on the newer models.

Another possibility is a bad battery. If the battery voltage drops too low when cranking, it will mess with the electronics. Have your battery load tested to see if it is good.

[Snake Ranch]

Originally Posted by Sabre-t

There are a couple of possibilities that I can think of besides the throttle bodies.

Do you let the electronics reset for a few seconds between turning the key to "ON" and pressing the starter button? The electronics need to reset before you crank it. Even blipping the throttle too soon after cranking will mess it up. This is especially true on the older Voyagers/Vaqueros. The electronics boot up much faster on the newer models.

Another possibility is a bad battery. If the battery voltage drops too low when cranking, it will mess with the electronics. Have your battery load tested to see if it is good.

Yes I allow the electronics to fully boot up prior to starting the engine. I replaced the battery about a year or year and a half ago. I can check it as it is easy to do. I can load test it.

Thanks for the response.

[Peg]

Originally Posted by Snake Ranch

... My question has any body been able to connect this code 18 to the problem where the engine will rev up by it's self after sitting when hot and not completely cooled down and not return to idle until IT gets ready to?
...

This part of your post intrigues me. Lately my own bike has been doing this intermittently as well. After a period turned off, when I start the bike again it will rev up to a fast idle for some time. Blipping the throttle has no effect, but mostly after a few miles, often while stopped at a red light, it will suddenly drop idle speed to normal. As with yours, cleaning the throttle body doesn't seem to have fixed the problem.

[redjay]

Snake Ranch and Peg, do you both have Ivan's flash ?

[Peg]

Originally Posted by redjay

Snake Ranch and Peg, do you both have Ivan's flash ?

Of course YES, and I'm used to the fast idle at startup. This is an entirely new and different thing, that I first encountered on a hot day during a long trip over our summer. Stopped for gas, and when I restarted the bike it was like the idle was reset at 1500 rpm's. Unless I pulled the clutch there was no slowing down coming up to intersections at all, and it felt like very little engine braking through all the gears.

When the bike feels like it, the idle speed suddenly drops to normal. The same thing has happened intermittently ever since then, usually following a restart within a few hours, particularly when the journey wasn't a long one to start with.

So far it's been a mildly unusual head-scratcher, but if it starts throwing up error codes I'll have to dig a little deeper into it.

[Sabre-t]

Possibly the throttle position sensor is going bad. Errors in the throttle position sensor will throw error code 18.

Since the water temperature is used to turn off the fast idle after the bike gets warm, maybe your water temperature sensors are going bad.

There are test that can be run on both of those sensors.

[plumber63]

Mine did what Pegs did last year while in North Carolina in late Sept. It was fairly warm upper 80s. I found my fan wasn't coming on, bike was running hot. The fuse blown. Replaced it, hasn't blown again. Seemed to straighten up. Didn't ride much after that last year. And just got it out today. Will have to keep a eye on it.

[Snake Ranch]

Originally Posted by Peg

Of course YES, and I'm used to the fast idle at startup. This is an entirely new and different thing, that I first encountered on a hot day during a long trip over our summer. Stopped for gas, and when I restarted the bike it was like the idle was reset at 1500 rpm's. Unless I pulled the clutch there was no slowing down coming up to intersections at all, and it felt like very little engine braking through all the gears.

When the bike feels like it, the idle speed suddenly drops to normal. The same thing has happened intermittently ever since then, usually following a restart within a few hours, particularly when the journey wasn't a long one to start with.

So far it's been a mildly unusual head-scratcher, but if it starts throwing up error codes I'll have to dig a little deeper into it.

Sorry I have been really busy, retired in September and I cant believe how busy it's been. Not much time to sit and read.

Anyway, I have the second flash. I have been able to purchase the extended warranty so I have an appointment with the dealer to check this out.

PEG, my scoot has the same symptoms as you describe. AND I do believe it's temperature related as the throttle speeds act the same with heat and time.

I don't have an appointment date till July 1 st. This COVID thing has disrupted the service departments around here. I intend to be present when they are working on my scoot, I don't intend to drop it off and walk away. Here is an opportunity for me to learn something about my skoot.

I have a bunch of questions about this issue and have not been getting straight answers from the factory or the dealer here in town.

The dealer here in town has just taken on the KAWA line from another shop in town. So they have a lot to learn. The dealer out of town has a young service manager who understands how to answer my questions and take the time to answer them.

I will relay what I learn when this gets resolved.

[VicenteRamirez]

Que genial, me encanta todo esto

[Snake Ranch]

So I was in San Francisco yesterday and on the way home I was not to far from the dealership that I go to. The service manager told me not to worry about anything if the problem has not reoccurred, which it hasn't.

He feels there is a link between the fast idle problem when the engine has cooled down a small amount from operating temperature. Although he doesen't have a lot of in-tell on the subject.

He did say the computer control module does take a snap shot of the code warning but it is very lacking in information for my year model.

He said the best thing is to keep riding and if it reoccurs then come in for them to check it out.

I believe he didn't want to waste my time and money for one occurrence.

The one thing I am struggling with is I have been getting about 44 mpg. And all of a sudden I'm getting 47 to 51 mpg. I don't know what to make of this and give it up if the throttle body is replaced an my mileage drops to something worse.

My question is, if I can get better mpg's some time why can't I get it all the time? Why, all of a sudden am I getting better?

[Sabre-t]

If it has only occurred one time a month ago, then the dealer may be right to say not to worry about it. Something could have confused the ECU and caused it to throw a false error code. Shutting down and restarting could clear the condition that caused the fault to be thrown.

[mbarr10]

I have never had the code 18 error, but after my transmission rebuild I went from 26mpg to 34 in town. With all the drama of the rebuild I have a hypothesis for my mileage increase. It might be the same for you?? I just ride different now. But I still have that sh*#t eating grin on my face everyday I ride. YMMV

[Snake Ranch]

Originally Posted by mbarr10

I have never had the code 18 error, but after my transmission rebuild I went from 26mpg to 34 in town. With all the drama of the rebuild I have a hypothesis for my mileage increase. It might be the same for you?? I just ride different now. But I still have that sh*#t eating grin on my face everyday I ride. YMMV

My grin is bigger when I'm getting that better fuel mileage.

But I like to understand why things work the way they do.

[mbarr10]

My smile is bigger with the lower gas mileage, Yet I still have a smile and good feelings inside when I ride every day. Better mileage may ( most likely ) help me live longer. And still will have a happy life. Just a bit longer of a happy life with good mileage#. The Vaquero handles so much better in the corners than my 1500 Classic, that I really enjoy pushing it harder. Kinda explains why I trashed 2nd gear this last year.
But as always YMMV.