|
|
| Stumbling/stalling at part throttle when cold: ideas? |
Subject: Stumbling/stalling at part throttle when cold: ideas?
by smellsofbikes on 2022/4/4 4:50:53
My engine's been starting and running a little rich, so today I checked the fuel level in the float bowl (about correct), and took apart the automatic choke to make sure it's working right.
I adjusted the auto choke so it's definitely closed when the engine is cold. I push the throttle pedal once to shift the lockout so the choke does close, and that pretty much floods the engine. It takes a LOT of cranking to suck the gas through (and the car reeks of raw gas) and then finally it starts. Until it warms up, I just have to sit at idle, because if I get on the throttle at all, it'll sputter and die.
In contrast, if the car's run, like, yesterday, and I don't push the throttle (so the choke is still mostly open) the car will start and I can get to fairly full throttle, but it still stumbles badly below like 2000 rpm.
As soon as the water temp is off the peg, the car behaves perfectly.
It also appears that the choke is opening fully well before the engine is warm, and I'm wondering if that's why it's stumbling so badly, although as noted I think it's running rich not lean, so when I open the throttle a bit I'd expect it would get closer to lambda and run better.
The accelerator pump is definitely working. I can see it spraying in fuel. I feel like it's working too well. (Kinda kidding: it works just fine when the car's warmed up.)
I'm a little tempted to put a manual choke on there for a while and see if I can adjust it to perform better, or whether it's not the choke but something else that's the problem.
Timing (with the vacuum removed) is right on, and pulling vacuum advances the timing, so as long as that tube's not leaking, I think the timing is okay.
It's weird. I mean, I'm glad it works fine when it's warm.
|
|
