manifold thing-a-ma-jig

iglou · 05-23-07, 07:39 PM

there's a thing on the manifold that looks like the drawing below.

where do the vac hoses that hook on to the larger and smaller opening on this thing-a-ma-jig go?

thx

2mbb · 05-23-07, 09:22 PM

The big port is connected to the brake booster. The small port goes to a VSV on mounted on the fender that is part of the AC idle up circuit

iglou · 05-24-07, 07:32 AM

does the small port still need to be connected to the vsv after a desmog?

beaufort-fj60 · 05-24-07, 07:34 AM

Quote:

Originally Posted by iglou

does the small port still need to be connected to the vsv after a desmog?

i put a rubber cap/plug on the small one, but i don't have a/c

2mbb · 05-24-07, 08:28 AM

Quote:

Originally Posted by iglou

does the small port still need to be connected to the vsv after a desmog?

The small port is not for a smog component for for the air conditioner. When the air conitioner compressor turns on the idle speed is increased. If you have air conditioning and the vacuum actuator at the front of the carb and the VSV then you should connect them up with vacuum tubing.

iglou · 05-24-07, 10:33 AM

Quote:

Originally Posted by 2mbb

...If you have air conditioning and the vacuum actuator at the front of the carb and the VSV then you should connect them up with vacuum tubing...

...per the diagram you provided above. great! thanks!!

and i thought i read somewhere that the best place to connect an in-cab vacuum gauge is to t-connect it from the small port. is that right?

RenegadeQ · 05-24-07, 03:01 PM

I would T-connect into the smaller fitting. That is my plan for my in-cab vac gauge.

iglou · 05-24-07, 08:57 PM

i re-vacced the small port and actuator on the carb to the vcv (per the diagram above). she drove great in the a.m.

on the way home, however, i decided to kick on the a/c to see how far the rpm's would drive up. the rpm's stayed steady, and i killed the a/c. as soon as i turned off the a/c, the engine died on me. i couldn't seem to accelerate past 1000 rpm without the engine wanting to die.

i rearranged things back to the way they were, and the engine was still acting the same way.

PLS HELP!

iglou · 05-25-07, 01:10 PM

okay, maybe this is a cheesy way to bump this thread to the top...

iglou · 05-26-07, 09:09 PM

Quote:

Originally Posted by iglou

on the way home, however, i decided to kick on the a/c to see how far the rpm's would drive up. the rpm's stayed steady, and i killed the a/c. as soon as i turned off the a/c, the engine died on me. i couldn't seem to accelerate past 1000 rpm without the engine wanting to die.

i rearranged things back to the way they were, and the engine was still acting the same way. PLS HELP!

can anyone help??

bram · 05-26-07, 09:29 PM

that vacuum line will only affect the idle speed with the AC on. You won't notice a difference if you are driving.

As for your main problem, when was the last time you tried to use your ac? Maybe the compressor clutch is malfunctioning or the compressor is not spinning freely. The idle up mechanism (pn88031 in diagram above) on the carb could be stuck, preventing the throttle from operating correctly. How much vacuum do you have?

iglou · 05-27-07, 11:52 AM

thanks bram. how can i unstick the actuator? should i spray it w/ wd-40?

bram · 05-27-07, 12:33 PM

Have you verified that is the problem?

With the AC off and the truck idleing, pull the actuator arm toward the diaphragm to simulate the idle-up. While you are holding it in this position you should hear the idle speed increase. Make sure the arm returns to its resting position freely when released and that the idle speed returns to normal. If all that works there is nothing wrong with the actuator. If it doesnt, then you need to find out why not. If rust or corrosion is the problem then WD40 should work. I would then follow with some lithium grease to keep it lubed. However, it is also possible that the linkage is bent or broken somehow. Or any of the other possibilities i mentioned before.

iglou · 05-28-07, 02:17 PM

Quote:

Originally Posted by bram

...when was the last time you tried to use your ac? Maybe the compressor clutch is malfunctioning or the compressor is not spinning freely. The idle up mechanism (pn88031 in diagram above) on the carb could be stuck, preventing the throttle from operating correctly. How much vacuum do you have?

i haven't been using the a/c at all. the problem began when i hooked up the a/c idle up and tried testing it. i've since then disconnected everything, but the engine keeps dying out on me. i dunno what gives?? i guess i'll go get a vacuum gauge and test the pressure.