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Wed Oct 13, 2004 6:29 pm

I have a stumbling problem upon stoplight take off. I have replaced the plugs, wires, cap and rotor. I am NOT running an 009 distributor as I have read that those can cause this type of problem. I rebuilt and cleaned the stock vacuum can distributor with fresh points, etc. I have adjusted the valves and I still have the problem. It HAD an older oil filled air filter canister replaced due to an engine fire. I recently have replaced that with an after market disposable filter. Therefore the charcoal canister was removed from the passenger rear wheel well. I don't suspect that this would be the cause of the problem, am I wrong?

One other thing to note is that it seems the problem is worse when it is damp or has been raining out. I can usually live with the problem when it's sunny and dry out. I thought it was a car not a sugar cube! So now in the past couple of days it just won't run at all. It seems like I have to tune this car more than drive it!

I would really appreciate any feedback/help anyone can offer.

Cheers,

Wed Oct 13, 2004 6:42 pm

I also checked the compressions and they are all within spec.

Wed Oct 13, 2004 6:45 pm

Probibly the carb needs adjustment.

Wed Oct 13, 2004 6:46 pm

I have adjusted the carb too many times for health. I even had a professional mechanic do it because I thought I was doing it wrong. It turns out I wasn't doing it wrong at all.

Wed Oct 13, 2004 6:51 pm

My 34 PICT 3 is brand spankin' new and not a rebuild. I keep forgeting all these small details.

Thu Oct 14, 2004 4:27 am

I will be watching this thread I am having the same problem mine started when it was raining and has not gone away. I am leaning towards a bad coil, it will just die like someone pulled the coil wire but it will start right back up. Mine won't miss except under load the valves, timing, carb, plugs, wires, and fuel pump are new and in tune it also has elect ign. and it's driving me crazy.
For a few days before it started my generator light was acting strange ?
My wipers stopped working this morning and all the fuses are fine ?

Thu Oct 14, 2004 4:37 am

I have the exact same problem. The car runs fine until I stop and try to accelerate. Carb is new and adjusted from a mechanic. I have a new fuel pump, hoses are new and the tank is clean too, etc....

Let's hope somebody knows what causes that.

Thu Oct 14, 2004 5:38 am

Have you checked the timing both at idle, and also at full advance? If the timing is not advancing properly upon acceleration, that could cause problems.

Thu Oct 14, 2004 10:14 am

Just picked up a new coil and Compufire module, I will see if that will fix it this afternoon.

Thu Oct 14, 2004 6:32 pm

I've been through this scenario. Remember, always try the cheapest, simplest thing first. But here is how I fixed it....after weeks of the frustration you're going through right now.

Checked for vacuum leaks in the intake runners. Ended up replacing the boots and intake gaskets. Didn't do the trick for me, but it helped a little.

Looked at the carb. Noticed it said "Bocar" on the side. Tossed it in a dumpster. Replaced it with a Solex. Problem solved.

Thu Oct 14, 2004 6:47 pm

Shane wrote: Looked at the carb. Noticed it said "Bocar" on the side. Tossed it in a dumpster. Replaced it with a Solex. Problem solved.

Bocar is Solex (Brazil)

Thu Oct 14, 2004 6:56 pm

Not to sound like an OG purist here, but....

All I know is that if it says Solex on it, it works. If it says Bocar on it, it's junk.

I've had three of those Brazilian made paper weights over the years. Found an old, beat up, dirty Solex in the bottom of my parts bin. Cleaned it up and it always worked.

Thu Oct 14, 2004 8:54 pm

i had a 30/31 on my super when i first got it, and i know what you are talking about, it had the worst flat spot :( , and mine was not only from a dead stop, well the carb started to leak :shock: , i tried to rebuild it, but for some reason that carburetor was a peace of junk :evil: , i bought two used Solex 34 pict 3 on this website for 40 bucks :wink: , rebuilt on of them, and slaped it on my engine and I have not had that problem ever since 8) .

Fri Oct 15, 2004 4:16 am

I am running a Weber 36DCNF and it works great, I have a set of Kads just haven't had the time to install them yet. I fixed my problem the coil did the trick but there was still a slight miss sometimes so I kept looking and found the Compufire module was just a little loose. Now it's screaming down the road as usual and running great. Now I need to find out why my wipers stopped working, ahh the joys of Volkswagen ownership.

Fri Oct 15, 2004 10:07 pm

If a car is dying when accelerating from idle it is sometimes related to the air filter being too dirty. Those little chrome replacement filters to replace the original are really crap.

Also a carb out of adjustment/bad fuel delivery.

When it is raining- if the car does not run the same one thing to suspect is going to be the spark plug wires being dirty. The dirt and moisture will cause the wires to have some voltage leakage causing weak spark.

Try spraying the ends of the wires with a light mist from a spray bottle when the car is running- if it start to run bad then the cables need to be cleaned.

Mon Oct 18, 2004 7:31 am

I know mine isn't a Super but I had the exact same problem with my 65. After I went through all the tune-up procedures with the strobe light, reading the book, setting the gap, and still I had stumbling.

Finally I said, hell with this, put the tools in the car, drove to a nice secluded road with plenty of places to pull over, and started to drive, stop, turn the dizzy, drive, stop, turn, over and over until the stumbling went away.

What I found was that if I turned the dizzy to the right just a bit each time (advancing the spark?), the stumbling would get progressively less, until it went away completely, but then the idle would start to get rough. So I kept adjusting it until I had the least stumbling with the smoothest idling. I've been struggling for years with my Super and my standard to get it right and this has given me the best results.

The other thing that caused stumbling in my Super (it had FI) was a loose air intake elbow (the big rubber elbow-shaped hose by the air flow box). Tightened that and the stumbling went away.

Mon Oct 18, 2004 10:06 am

With that carb the stock aircleaner is a must along with the all the pre-heat tubes hooked up and working. IE. from the exaust to the intake and the "stove-pipe to the aircleaner. then make sure they work.Aalso if you noticed the generator light doing strange things then you need to make sure all the grounds and electrical conections are good and solid. Might even be a prob with the voltage regulator.

Mon Oct 18, 2004 2:02 pm

I never had my stock air cleaner. It came with an oil filled air filter canister because the paper one melted due to an engine fire. I took out that oil filled canister and replaced it with one of those stupid chrome cheap replacements. I'm going to look at getting a stock paper air cleaner assembly. Maybe that will fix my headaches.

Thu Oct 28, 2004 11:33 am

I have same problem with BOCAR carburator. Idles good, but let the clutch out in 1st gear and try to accelerate and it stumbles and gags, after a couple tries it finally will accelerate through the gears. I have all new parts...carb, fuel pump, coil, wires, petronix elec ign, heads, cylinders etc. A local VW expert from the late 60's said my idle jet is too small and needs to be reamed out. He has a set of German jet files to accomplish this. I have a box of old Solex carbs that I have been saving so I removed the Bocar idle jet and the Solex idle jet and found that by looking at them both side by side the Solex idle jet had larger holes in it. I tried putting that jet on my Bocar carb and it does run better but not perfect yet. I am going to try the file next!

Fri Oct 29, 2004 12:38 pm

Hi
Ive had the same problem with same carb that was recently rebuilt. It tunrned out that there must have been dirt in the fuel system that plugged passagas in the carb. There are 4 very small orfices in the bore of the carb by the throttle plate if one is plugged you will have a flat spot on acelleration as the transition from the idle circut to the main running circut is poor. It took me three days of soaking the carb and alot of compessed air. The car runs fine now. I now have 2 inline gas filters.One on the tank outlet and one after the fuel pump.