[bs1231]

First, Thanks for stopping at this thread.

I'll try to make it a short story...it's been a long time and lot of work for me to get this far.

1985 pick up, 2 WD, 22R, Carb, 205K

So far I have done:
New Plug Wires
New Plugs
New cap and Rotor
New Intake maifold gasket

The fuel filter was replaced 2 years ago. The carb was rebuilt 2 years ago. When this problem started, I went back to the shop that did that, carb was checked OK, fuel tested OK. It cost me 150 bucks.

Top end rebuilt before I got the truck at 165K

I have over 200.00 into this problem with zero change. Through this process I have eliminated what it isn't. I just can't figure out what it is!

I am at the end of my finances and my knowledge/ability. I could really use some help.

It acts (to me) like it has a vacume leak, but I can't find anything.

Here is a link to a youtube video of me spraying carb cleaner trying to find a vacume leak.

http://youtu.be/eBsb_gyRImY

Thanks again!
Brad

 

[fourwd1]

While you did provide a lot of info on what you've done, you didn't provide much on the problem itself.
"idle problem" is pretty vague, can you give us some more details?

 

[bs1231]

For some reason I didn't get the usual email notification that someone responded. I finally checked in today and found your reply.
Thanks for the comment, I thought the video I took might provide the information as far as explaining the idle, so folks can see and hear what it's doing. Were you able to click on the youtube link and see my video of it idling?

Any other feedback appreciated.

 

[longbed]

idle problem

It sounds as if it is "surging"; when it's running what does the fuel level look like when viewed through the sight glass; should cover half of it).

I would start with the idle mixture screw and make sure it is adjusted right.
If that doesn't do it then:

Get a vacuum guage and check that both vacuum cans on the distributor body hold vacuum; all pull vacuum on EGR valve (it should die when opened at idle).

Did the shop re-install the carb? check the mounting bolts where it mounts to the intake manifold and that all vacuum hoses are secure and in good shape.

 

[Rh1n0_86OneTon]

It sounds like the carb is running on the primary booster and not the idle circuit. These carbs are set up with angles and not clearances so they are a bit of work to get back right once screws have been messed with. I am not a fan of going for the mixture screw first as that is rarely the issue. I'd do this stuff one at a time:
1. Get a factory shop manual
2. Replace all the soft vacuum lines. Pay attention to the orientation of the orifices (yellow/black or clear/black) in the vacuum lines and put them back correctly. The lines get hard over time and the sum of all of them leaking a little bit can add up to quite a leak. Get metric hose from your local VW supply shop. Don't use the SAE stuff. It will leak. You will need about 10 feet of line. 3mm/2.5mm Don't recall which. Bring a sample.
3.Test all the diaphragms on the carb and vacuum switches.
4. Remove the carb and set it up like the manual says. Also check for carbon deposits or leaks/clogs. High E guitar string is a great poker for the little ports.