I need the vacuum diagrams for a 1976 GMC Sierra with the Rochester Quadrajet 4MV carb. My father in law has the distributer hooked to the small diametter long tube that comes out of the side at the c

SOURCE: My 2003 GMC Sierra Idles Rough And Cut Off

Before replacing the O2 sensors, I would check the fuel pressure. You may also try to have someone pull a trouble code from the powertrain control module to verify why the engine light is on. Do not replace any parts until this is done, otherwise your going to be guessing at the root cause, and it will get expensive with part replacement.

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SOURCE: need carb assistance, seems like choke is not

1. Check the "anti-diesel solenoid" fuel cut solenoid. The solenoid should click when it has a power and ground applied to it. Remove the pintle and put the solenoid back in. If the idle circuit it OK, the engine should idle. If it does, then there is a problem with the solenoid. If it still wont idle , the idle circuit in the carb. Could be clogged.
--------- start removing carb and refitting.clean the carb and readjust the choke and idle. ----------To get instructions to do this.Please click on the link below:--- http://technoanswers.blogspot.com/2011/06/choke-is-not-working-on-nissan-king-cab.html -------------------- This should help.thanks.Helpmech.

SOURCE: Emissions sticker under hood is

if this car has a 307 with a carb it did not come out with it the 1989 fleetwood came out with a 4.5L cadilliac V8 with DFI fuel system, so i have no idea whet to tell you on the vacuum lines.

the last year cadilliac used the 5.0L (307) was in 1986, and they used 2 fuel systems so you need to know your vin# the 8th vin# will be either a Y or a 9

vin# Y



vin# 9



now for adjusting the carb. if it has never been adjusted before you will need to remove the carb and turn it over and remove the factory plugs over the adjusment screws then reinstall the carb and using a double D adjustment tool turn the screws out 2 turns then start turning the screws in one at a time untill the rpm drops then back back out just untill the rpm leves back out then 1/4 more this is called a lean drop carb adjustment also this carb has a mixture control unit inside the carb and it can also be adjusted but you need a dwell meter adjust the mixture control unit to 30 degress dwell on the V8 scell.