Thread: 350 Barely Idleing

Tweet

My 350 doesn't idle right, yesterday I took it for a ride to my families house and on the way there I realized that when I let off the gas for a stop sign or just to slow down the engine sounded like it was just barely idleing about to die which doesn't make sence, when I started it up to go over there the idle was just fine at 800rpm's.
Once I got it home I checked my rpm's again and it was slow but even when I speed it up it still sounds the same until about 1100rpm's, it sounds like its chocking or bogging down to me but I have no idea how to fix it, tried everything I could think of and no go.
Please help

Originally posted by dcurtis
My 350 doesn't idle right, yesterday I took it for a ride to my families house and on the way there I realized that when I let off the gas for a stop sign or just to slow down the engine sounded like it was just barely idleing about to die which doesn't make sence, when I started it up to go over there the idle was just fine at 800rpm's.
Once I got it home I checked my rpm's again and it was slow but even when I speed it up it still sounds the same until about 1100rpm's, it sounds like its chocking or bogging down to me but I have no idea how to fix it, tried everything I could think of and no go.
Please help

make sure the choke is open all the way.

Sounds like a vaccume line has popped off,,,or you've developed a Leak in either the carb base plate gasket,,or intake gasket.
Have a good look see,,,and tighten and check all the hose connections,,,take a look at the Vaccume advance module on the Distributor,,make sure it's not leaking,,,and is advancing as it should.
If non of this corrects your problems,,,then get a small propane torch,,,and start your engine,,,then turn the propane torch on without being lit,,,then direct the gas to-wards the intake manifold to head seams,,,,same for your base plate on your carb,,,and if the RPM increases then you know you got leak because the propane gas will be sucked into the bad seal,,and will add fuel vapour to your engine which will increase the RPM.
P.S. also check the Vaccume host going too and from your brake booster,,,this one is the biggest vaccume lines you have.

Oh yeah,,,,do the simple thing first and check your choke.. LoL
And if you still cant get it running right,,,then do the tests i suggested.

Chokes broke it stays open 24/7

It used to only do it once in a while but now its consistent.
The motor only has about 100 miles or so on it, the old motor done this also

if you put the palm of your hand over the top of the carb opening,,,and the RPM increases,,then you will know for sure,,it's fuel,,,or Vaccume related.

No more problems, I found a leak right behind my carb where a vacuum line screws into it at, it was just loose. Hard to think that I've been looking for that leak since I bought the truck a year and a half ago. Thanks

Yeah,,,i especialy like the ones where the rubber vaccume hose develops cracks on one side, just where you cant see it,,,and most of the time is sealed ok,,,but once in a while the rubber hose gets moved througfh engine torque,,and then loss of Vaccume occurs.
I've seen problems like that "Stump" some of the Best Mechanics in the game.