Honda Elite 110 - idling issues

[dexameth]

So my Elite 110 has been super reliable and trustworthy... up until a few weeks ago. Starts and runs amazing but will throw a IACV (Idle Air Control Valve) malfunction code. It will still run, but will idle at random rpms when it's set to idle at 1900 for warm up and 1700 after that. It's even stalled a few times when coming to a stop.

When the problem first arose, I installed the throttle body from my spare engine and it threw the same code and idled funky. So then I got my service manual out and checked the volts - everything was within spec. Cleaned all connectors and it still threw the code and idled wrong.

So today a guy drops off the same scoot at my shop. Tank full of water, tires flat, it's been sitting for quite some time. I swapped my ECU for his (I couldn't have gotten so lucky to get to test a different ECU). SAME DAMN CODE.

So now I'm a little worried. The wiring is showing good volts and all "new" parts installed... I gotta go deeper. I think there's an air leak somewhere making the IACV try to work against the air leak and now it acts like a bad carb.

Next to check the intake insulator (if there is one, never had to pull the intake yet) and also the vacuum line going to the fuel tank vapor emissions. It's gotta be one of those...

[dexameth]

Did a little more tinkering and found the issue.

First I blocked off the vacuum line then I started and warmed up the engine and waited for the code to go off (engine light flashes). It did.

I then turned off the engine and did the voltage test again. There's 4 wires going to the IACV and sure enough the grey/red wire is getting .4v when it should be 1.8-2.2v. The other wires tested in range.

I went up to the ECU, found the grey/red wire and tested the volts there... only .5v! WTF? Another IACV wire tested on the ECU read within the range. Now I'm confused but I think I got it: the grey/red wire is grounding out somewhere. My cheapo volt meter actually doesn't have continuity check but it has ohms, and I get a reading between ground and the grey/red wire. I shouldn't have any reading at all, right?

My next step is to try to re-wire the grey/red from the ECU back to the IACV. I can snip the wire at each end and run just a single external wire between the two. This should rule out any ground out. I have my fingers crossed.

[dexameth]

I got it all sorted out! Just as I thought, I had a wiring ground-out. I was getting ready to splice the external wire and saw this:







The wiring harness was not in its' clip, but next to it. The water tube was pressing into it for so long the clip actually dug into the harness and cut not only my IACV wire but the O2 sensor wire. Weird as my ECU never thru any O2 code.

Got them both rewired up and on my drive home from work it ran SO MUCH FREAKING BETTER.

Back to 100%

Now to hit 70,000 miles on this 108cc


I hope anyone else having weird issues can use this as a pointer to check and double check all your wires, and make sure they are routed correctly!

[jbjhillbilly]

Always start with the little stuff, right?

Glad you sorted it out!