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Sun Jan 09, 2005 8:09 am

Replaced the carb (dual port w/ 34 pict 3, stock dizzy) I replaced all the intake gaskets, boots and carb gasket. the old one had bad throttle shaft, so I rebuilt one. Got it on adjusted it 2 1/2 turns out, big screw 3 turns, timing is great, runs great idles at 1000 RPM for about 10 seconds and then is dies slowly. I played with both of thescrews and can't get it any better, so I put it back to where I started. I am unable to get it to stay idling. When I was messing with it I accidently knocked off the vacum plug on the intake and the idle went up for about 5 seconds and then it shut off, I put the plug back on off course.
Where do I go from here?
Do I adjust the big or the little screw? Out or in?
If it runs lean the motor can over heat, right?
No local VW mechanic available to me so the best I got is you guys

Sun Jan 09, 2005 8:36 am

Make sure the idle selenoid on the other side of the carb is working. Turn the ignition switch to the on position ,(do not start) then go back and remove the wire (will be black unless replaced) and touch it back to the selenoid spade that it came off of. It should make a slight click noise when it has 12 volts applied to it. If not replace it or take it out and cut off the plunger end, then put it back on if you need the car till a replacement can be purchased. If no wire is to it then connect one from the + side of the coil to it .

Sun Jan 09, 2005 8:52 am

read step 5, adjust idle
that was the problem for me.

http://www.vw-resource.com/tune-up.html#idle

this is the site that it came from, lots of good info.
http://www.vw-resource.com/

Sun Jan 09, 2005 9:32 am

Ok, here is whats going on. I checked the solinoid, but wasn't sure if it works ( I have bad hearing) so I had an old one that i trimmed the end off of to see if that is the case. Put it in and it fired up idled around 1500RPM then as it warmed up it dropped to 1200 RPM and stayed there for over a minute then the RPMS fell fast and it shut off. I started it up again, went through the carb adjustment procedure,it won't idle below a 1000 RPMs, it will idle at 1200 RPMs but after a minute or two it still shuts off by losing RPMs
Would a timing issue cause this?
advanced? or retarded?

Sun Jan 09, 2005 9:48 am

I'm having the same problem. I am going to rebuilding another carb(30pict). I was also told a clog heat riser can cause this problem. I haven't took mine off an cleaned it yet.

I think my adjust screws on my old carb may have been wallered out to much by the PO.

Sun Jan 09, 2005 9:52 am

If just finished dialing in, (and learning about a progressive carb). Playing with the jets had me taking the carb off a couple of times and the top plate off about a dozen times.

At one point, I had an irratic idle. It would idle fine at about 1200 for about a half minute, then drop to about six hundred. Eventually it would go back to 1200 and continue to cycle. I looked at a lot of things but found that this fault was a leaking intake manifold gasket.

Timing should not cause this issue, but I am just learning at this stage.

Mark

Sun Jan 09, 2005 10:27 am

My does not get erratic, it just falls till it shuts off. A thought just passed my mind, does the intake bolts need retorqued after it warms up. it does run better cold then it does warm

Sun Jan 09, 2005 10:45 am

My problem exactly. She she's warm and then dies.

Sun Jan 09, 2005 10:47 am

If I figure mine out, I'll let you know what it is

Sun Jan 09, 2005 9:46 pm

Adjust the valves to be sure they aren't too tight and causing the car to lose compression as it warms up.

Before doing the idle adjustment you are allowing the car to warm up and then adjusting it and not adjusting it right after it starts up.

If the idle drops after it warms up then your choke is working properly, but it should not cause the car to die, unless you have the idle set incorrectly to begin with,

Set the idle high so the car can warm up properly then adjust the idle to the proper setting.

Also test your choke to be sure it is working properly.

Mon Jan 10, 2005 7:13 am

I just adjusted the valves about 30 miles ago, I am also letting the car warm up before I try to adjust the carb. Whats happening is when the car is warm I start it up and it idles great for over a minute before it dies. I have started it up and made sure the choke is wide open (warm engineof course) and it is, so its not the choke. but it doesn't matter what I adjust it will not idle longer then a minute or two but i can take it for a drive and it drives great, lotof power (for a beetle). I was thinking of the intake gaskets i replaced, they was the metal ones, so I am going to put in the thick paper ones and see if that does it.