dying at stop; LOW idle By OMN (Read 3,671 times)

[OMN]

i like that mini set. may have to go to autozone.
thanks, alleyoop!

[OMN]

ok here's what i did tonite:

tried to adjust the a/f screw but didn't have much luck. i couldn't get it to turn more than about 1/4 turn while the engine was running. idle didn't change much. a little, but not much. i was able to rotate the carb (engine off) and adjust it but that didn't seem to change idle speed. which varies so much anyway, it's hard to tell if changing the a/f screw is doing much.

took the CVT cover off, removed variator. wanted to see if maybe a weak clutch spring was the issue. seems to idle along better, right around 1900-2100rpm. but still varies. sometimes it will rev closer to 3000, then come back down. if i leave it alone, it will slowly reduce its idle speed (like over 3-5 minutes) and then after about 1600 it will slow to a chug and then die.

if i gunned it several times or opened it up to 6000rpm then let off the throttle, it would quickly fall under 1500 and then die.

also sprayed everything with soapy water, as suggested. i don't find any bubbles. sprayed the heck out of it while running at 2000rpm - same story - no change in idle speed. so this makes me think there are no air or vacuum leaks.

i noticed that if i disconnect the air cut-off valve, the rpms jump immediately. same with disconnecting the vacuum line that runs to the fuel tank. could my air cut-off valve be restricting the vacuum and causing the fluctuating idle speed?

so i'm thinking fuel delivery. fuel pump, maybe? it seems like it's not keeping up. though when i used an auxiliary tank the other night, it just flooded.

a couple months ago when we did the PDI, i took the carb off and cleaned all jets and passages, so unless some new chunk of crud worked its way in there, i don't think it's the carb...

any other thoughts? thanks so much for the help! i'm about to try to post a video that i took of the idle speed fluctuating.
thanks,
ron

[OMN]

here's the video i shot of the idle going up and down on its own...
ron

[OMN]

thanks for the help so far. any other thoughts?

my plan is to take the carb off and re-clean it, then maybe try a new fuel pump if that doesn't do it. just thought of this - maybe i'll hook up some clear hose to the carb overflow and watch the fuel level, too. any other ideas?

gracias,
ron

[jct842]

Spraying with soapy water is NOT going to show leaks as bubbles. The leaks you are looking for are vacuum leaks and any bubbles would be inside the manifold not on the outside. Plain water will work, but I use carb cleaner or ether as they are thinner than water and will find a smaller leak.
Any change in engine speed denotes a leak, either up or down. john

[OMN]

ok, we may have figured it out. i took the carb off to clean it again, figuring that's about the only thing left. found a 1/4"-long piece of grass in the fuel inlet, between the hole and the needle valve. (see pics) cleaned it up and reinstalled - seems to be idling crazy good.

so there you go - great reason to use a freaking fuel filter!!!

thanks for everyone's help!
ron
;-P

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