New carb won't adjust
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Senior User
Joined: Feb 2000
Posts: 335
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From: Hutto 20 mi. above Austin USA
New carb won't adjust
Hey guys! I've got a problem with my truck, when I first start it in the morning, it will NOT keep an idle until the engine is warm, than it'll idle at about 600-700 rpm. Once I drive down the road about 5 miles or so, the idle won't go below 1100 rpm. I pulled over one day, to see if the linkage was stuck, and it wasn't. I don't have my manual choke hooked up yet, i'll do that today. I've checked my idle screws, and they're backed out so far that they don't even touch the linkage on the carb any more. My throttle linkage ( to gas pedal ) isn't so tight it's holding it at part throttle either.
What's up with that?
I already tried using some RTV on my spacer top and bottom, but i don't think i put enough on to make a difference, i'm going to try again today.
Oh yeah, and when you first start it, if you hold the gas at about quarter throttle, you can see the tach pace between 1100 and 1500, without moving your foot!
Chris A.K.A. Steakman
1982 F100 Flareside
Blue and Silver
31x10.5 BFGoodrich A/T K/O's
300 I-6, SROD 4speed, 2.75 9" Rearend
Edelbrock 500 CFM, Offy C-Series Intake
Clifford Performance Dual Outlet Headers
MSD6AL, 8.5mm, MSD S/C Wires
MSD Blaster 2F Coil
220,000 Original Miles
FM40 Series Duals Out Passenger Step
What's up with that?
I already tried using some RTV on my spacer top and bottom, but i don't think i put enough on to make a difference, i'm going to try again today.
Oh yeah, and when you first start it, if you hold the gas at about quarter throttle, you can see the tach pace between 1100 and 1500, without moving your foot!
Chris A.K.A. Steakman
1982 F100 Flareside
Blue and Silver
31x10.5 BFGoodrich A/T K/O's
300 I-6, SROD 4speed, 2.75 9" Rearend
Edelbrock 500 CFM, Offy C-Series Intake
Clifford Performance Dual Outlet Headers
MSD6AL, 8.5mm, MSD S/C Wires
MSD Blaster 2F Coil
220,000 Original Miles
FM40 Series Duals Out Passenger Step
Junior User
Joined: Apr 2001
Posts: 92
Likes: 0
New carb won't adjust
Sound like a vacuum leak to me. Pull the carb and spacer and use new gaskets, then plug all the vacuum lines from the vacuum tree on the side of the manifold. Start the truck and see how she runs. Then start replacing vacuum lines until you find the leaky one.
Is your truck engine computer controlled? You may have a leaky solenoid valve.
Is your truck engine computer controlled? You may have a leaky solenoid valve.
Senior User
Joined: Sep 2001
Posts: 169
Likes: 0
New carb won't adjust
Definately sounds like a vacuum leak. You can check by spraying carb cleaner around areas you think may be causing it. I always say, "check first, when you know, then change" When the carb cleaner is being sucked in the leak the engine will idle down some. I know you can't use this trick on and EGR valve or a leaking vacuum advance or solenoid, (those you can disconnect and plug the vacuum hoses to test) but it will work on your intake manifold and carb base. The EGR is a different story completely if it is stuck in the open position. It's a bit harder to plug. If you spray the manifold and and carb base, disconnect and plug the vacuum lines and you still have a massive leak, it could be a stuck EGR. Use a vacuum gage to tell. Herman
