2003 Goldwing Idle Issue

[yello mello winger]

I have a 2003 Goldwing and the bike started to run bad at Idle. I got the code from reading on the bike. It said it was the right knock sensor. I replaced both right and left sensors and no change, I got the same reading and the problem still existed. Talked to a dealer and they said replace the fuel pump. I replaced the fuel pump and it started up fine. I took off to test drive and again it would not stay idle. My next approach is changing Engine Control Module, but before I do, does anyone have any advice because I'm assuming the Engine Control Module is expensive and I already struck out twice.

[GoldWingrGreg]

Pull the shelter and both center cowls and look for any chew marks from a rodent. If poor running, wanting to die at stops is the issue, most likely it is a failing ECM. Unfortunately, the DNA in all ECM made back then are telling them to die. The part number is the same for all 2001-03s. So to test, if you have a riding buddy, with a Wing from those years, do a test ride with his installed in your bike. But, most will not act up unless the shelter is reinstalled. Whatever you do, do not waist your money buying a used one. It's DNA is telling it to die too.

The ECM is part #12.

https://www.mrcycles.com/oemparts/a/hon ... ntrol-unit

It seems like they have dropped in price. If I recall a few months ago they were a lot more. If you end up replacing the ECM, be sure to check the spark plugs. A failing ECM can foul them.

[tamathumper]

What, in particular, is failing in these vintage ECMs?

[GoldWingrGreg]

What, in particular, is failing in these vintage ECMs?

On this end, meaning the GoldWing repair industry, nobody knows. Like many vehicle control modules, the printed circuit board are slid into a plastic shell and epoxide closed.

[tamathumper]

So these are "fully potted" units, makes sense on a bike exposed to the elements. Probably rules out tin whiskers, too.

The ECMs started failing years ago in Porsche 944's, and a few now in the 968's because they're from the late 80's and early 90's at this point, and located in an area prone to moisture, heat and vibration. There is/was an aftermarket for resoldering them, but eventually someone just made a whole new one instead.

[Asphaltmaniac]

Pull the shelter and both center cowls and look for any chew marks from a rodent. If poor running, wanting to die at stops is the issue, most likely it is a failing ECM. Unfortunately, the DNA in all ECM made back then are telling them to die. The part number is the same for all 2001-03s. So to test, if you have a riding buddy, with a Wing from those years, do a test ride with his installed in your bike. But, most will not act up unless the shelter is reinstalled. Whatever you do, do not waist your money buying a used one. It's DNA is telling it to die too.

The ECM is part #12.

https://www.mrcycles.com/oemparts/a/hon ... ntrol-unit

It seems like they have dropped in price. If I recall a few months ago they were a lot more. If you end up replacing the ECM, be sure to check the spark plugs. A failing ECM can foul them.

Is this a problem with the 04 model as well???

[yello mello winger]

what is the gone down price your talking about? 900?? or so...

[AZgl1800]

Pull the shelter and both center cowls and look for any chew marks from a rodent. If poor running, wanting to die at stops is the issue, most likely it is a failing ECM. Unfortunately, the DNA in all ECM made back then are telling them to die. The part number is the same for all 2001-03s. So to test, if you have a riding buddy, with a Wing from those years, do a test ride with his installed in your bike. But, most will not act up unless the shelter is reinstalled. Whatever you do, do not waist your money buying a used one. It's DNA is telling it to die too.

The ECM is part #12.

https://www.mrcycles.com/oemparts/a/hon ... ntrol-unit

It seems like they have dropped in price. If I recall a few months ago they were a lot more. If you end up replacing the ECM, be sure to check the spark plugs. A failing ECM can foul them.

Is this a problem with the 04 model as well???

I have a 2002 gl1800, and the ECM was reporting a Knock Sensor failure.
Tests revealed the knock sensors and cables are good.

I found a 2004 bike that had met up with a metal/concrete firewall.
I bought the ECM and alternator, both are good, and the ECM is in my 2002 and doing fine.

So, all 2001 thru 2004 for sure, are the same, and I suspect the 2005 also as it is a Gen I model.

[GoldWingrGreg]

Is this a problem with the 04 model as well???

Yes ... 2001-2005.

[yello mello winger]

If I swap out the old ECM with the new one, Is that it? It doesn't have to go to a dealer shop machine to be set or anything like that?

[yello mello winger]

If I can just swap it out, anyone know where to find one from a wrecked Goldwing?

[bstig60]

Check MC SALVAGE YARDS.

[GoldWingrGreg]

Don't waist your time with used ECMs, ECMs from 2001-05s are all dyeing. Buying a used one is buying one that is almost dead too.

[lgjhn]

I have now replaced 8 of these over the past year for customers.
IF one gets a knock sensor code, especially the right side, it is likely the ECM 99.9% of the time. As one of my close tech friends said: "IF you actually find a bad knock sensor on a GL1800, you best frame & mount it on the wall as it will likely be a first."
FWIW, I've successfully put an '05 ECM into an '03 primarily due to the cost differences (the cost difference between years was originally huge), but now mother Honda has ALL of em priced sky high. I would not suggest going the opposite direction (an '03 ECM in a '05 due to emissions issues). I also would not risk a used ECM, but one can always take their chances and give it a try.
The theory behind of why this happens is that the ECM board was encased in an epoxy material inside the plastic case. That material, although somewhat hard when it was new, had some flex/give to it. As the bike ages and the heat cycle count builds up on the bike, that epoxy material becomes harder with less flex until it pulls a connection loose, usually it's the right side knock sensor connection thus giving the knock sensor code.
Replacing these is not overly hard. That ECM case is held in its bike housing by a small shoulder clip in the front. However, I must caution anyone attempting this that there are 3-4 terminal connectors, including the large ECM connector, that will need to be disconnected, and they can be extremely fragile due to heat/age etc. IF one of those happens to get broken, it's not fun to fix (don't ask me how I know). The new ECM costs are now sky high, but the wiring harness itself must be made of pure gold. Hope this helps someone.

[tinwacker]

I have an 04 gl1800 with 343 thousand on it and I have replaced my main computer twice. Once with a known good from my buddies bike that was wrecked . It lasted about a year, then a new one. Both times I got a code for a knock sensor. I also have several friends that have gl1800 and the same issue they get a knock sensor code and I replaced them no good. Then replace the computer all fixed . So now when I get that code I explain and usually just replace the computer and that fixes it

[smithtronics]

I have Replaced two also on my 2002 GL1800. Both delivered F1 code for the right knock sensor. Rough idle but operational. Both times the failure happened during a ride with High out side temperature 98+ Deg.
After swapping the Knock sensors, without any change in the error codes, I purchased a used ($300) ECU with a one year square trade warranty. The factory original ECU quit in 2017 the first used one lasted two years till 2019. The second used ($370) one is currently working with a few days left on the warranty.
Identifying a correct ECU for the first generation GL1800 is confusing, I have not looked at a list from Honda showing the part numbers available for these early units.
Bike Bandit and some others have a "where used" list showing all Honda motorcycles models that can use a particular part number.