Engine cuts out intermittently, at 50-55 mph (indicated) - 2006 People 150

[scott.mcg]

It's sudden, cuts out for about a second, or less. I suspected fire over fuel, because it quits, then resumes again, suddenly. It doesn't slow down, it's like turning it off for a second, then back on. Makes for a jerky ride just when I want speed.

But wait! I found that I could make it cut out predictably by going at less than full throttle, then goosing it to full throttle. Immediately after gunning it, it will cut out for a half second or so. Then it's back to normal.

Is this the overfilled gas tank issue? The seller, a friend, seems to think so, and said he had overfilled the gas tank more than once. If so, how to fix please?

(I will test for vapor lock tomorrow by loosening the gas tank cap - is this behavior consistent with vapor lock? Not sure what that does.)

At full throttle, going at an indicated 50 mph, it will keep cutting out intermittently. Very rarely under 50 mph. My initial instinct was that it vibrates an electrical connection loose (occasionally) at that speed, because of vibrations and stuff.

But wait! If I back off the throttle a bit, it will run smooth, still at about 50. Implying fuel, more than fire, it seems.

I'm pretty sure that if it was smooth at full throttle, I'd get a faster top speed.

Not in California, so any modification tips for more power would also be appreciated. A converter I could remove or something?

Cheers!

Scott

PS - former owner is a motorcycle / scooter guy, who knows about cleaning air filters, probably used Seafoam, etc. Someone he talked to suggested the emissions canister / overfilling gas tank thing. Could not find "emissions canister" in the 186 page PDF service manual.

[DMblues01]

Cutting out at full throttle like that sounds like it's hitting the rev limiter. But, on a 150, you should be hitting 65 mph or so on the speedo  before that happens.

I'd first change the fuel filter and air filter, just to address the simple things first.
I'd also check if the auto choke is malfunctioning and causing it to run too rich, since it smooths out when you back off the throttle.
Maybe check if the carb needs adjusted.
Also, ask the friend you bought it from if the cvt components have been serviced, or are due for service.

Beyond that, you need someone smarter and more experienced than me.

[scott.mcg]

Thanks, DMblues. I didn't think filters, because it's such an on/off issue, not a bogging down effect... nor any limiter or governor, because it can happen at 50, then go faster and keep happening intermittently.

I didn't think of the auto choke, though.

I didn't know it had a limiter, do you know a way to adjust or disable that for more power (without damaging the engine)?

Thanks for replying, and for some new ideas to check!

Scott

Cutting out at full throttle like that sounds like it's hitting the rev limiter. But, on a 150, you should be hitting 65 mph or so on the speedo  before that happens.

I'd first change the fuel filter and air filter, just to address the simple things first.
I'd also check if the auto choke is malfunctioning and causing it to run too rich, since it smooths out when you back off the throttle.
Maybe check if the carb needs adjusted.
Also, ask the friend you bought it from if the cvt components have been serviced, or are due for service.

Beyond that, you need someone smarter and more experienced than me.

[scott.mcg]

I did briefly test for vapor lock by loosening the gas cap and getting up to speed. The issue recurred, but it seemed like it did it a bit less. I could still make it happen by gunning the throttle when indicating over 40mph.

I may end up paying for a tune up if I don't find a simple solution.

[tortoise]

CDI ice trick.

[scott.mcg]

Cool, tortoise, good to know, thanks. It does not seem to change with heat, distance or time, though, just speed; the behavior is pretty consistent.

If there is something about the CDI that makes it heat up right around 50mph, that could be it, I suppose, because I can drop down to 45, and it doesn't do it. I don't know exactly how the CDI works.

But that link, and the descriptions of CDI issues, seems very close to what I have experienced. I may try installing a new one.