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Sun Aug 10, 2003 5:57 pm

Can anyone explain why my bus continues to run after I turn the ignition off? It seems to be getting progressivly worse over the last week. Today it went on for about 30-45 seconds maybe.? The only thing I can think that would be causing it is my messed up carb.

Thanks

Sun Aug 10, 2003 6:41 pm

Actually..sounds more like a ignition switch problem. Ever have a hard time to start up?

Sun Aug 10, 2003 6:48 pm

Without knowing what year bus you have, I can only guess.

First place I would look is at the carb to see if the wire that connects to the little electromagnet on the right side has been disconnected.

Sun Aug 10, 2003 7:52 pm

When you say it won't quit running, do you mean like you never even turned the key off, or is it like sputtering and still kinda half running for a few seconds. If the later is the case, you have what's called "dieseling". It can either be caused by, as previously mentioned, a poor electro-magnetic carb solenoid, incorrect ignition timing, or hot spots in the combustion chambers of your engine, likely caused by carbon buildup. Describe to us "how" it runs after you shut the key off.

Mon Aug 11, 2003 8:40 am

Its a 71 and yeah it kinda half runs and spudders when I shut it off. It has to be the electromagnetic choke mechanism on the carb, cause I have to get out and move it after the bus has heated up for awhile during cold starts. The choke is all rusty, can I order just a new choke mechanism for that and put it on?

Mon Aug 11, 2003 10:06 am

Mine did the same thing and after i replaced the "dieseling" valve it stopped it completely, it actually screws into the side of the carb behind the choke and has a wire connector that you can splice into the choke. It could be a number of things also like the other thread stated. good luck anthony

Mon Aug 11, 2003 10:16 am

So how bad is this for my engine? If it goes on for say 1 more week?

Mon Aug 11, 2003 10:28 am

I would imagine it is not too good for the engine, because what that jet does is it stops extra fuel from being dumped into the engine once you turn the key off. Even when it runs on and stops it probably still is trying to burn all that excess fuel and sometimes it might not burn it all and my guess it would start washing the oil off the cylinder walls, just a theory. anthony

Mon Aug 11, 2003 10:33 am

Mabey someone could tell me which is harder on your engine: letting it diesel until it stops, or doing what I have done in the past which is to put the vehicle in gear when I stop and slightly let up on the clutch until the engine has a pull on it then cut it off. It never diesels that way but is it harder on the engine? To me nothing sounds more ghetto than a run-on engine. Dave

Mon Aug 11, 2003 11:42 am

farmersdahtr wrote: Mabey someone could tell me which is harder on your engine: letting it diesel until it stops, or doing what I have done in the past which is to put the vehicle in gear when I stop and slightly let up on the clutch until the engine has a pull on it then cut it off. It never diesels that way but is it harder on the engine? To me nothing sounds more ghetto than a run-on engine. Dave

I have known many people who have "solved" a deiseling problem by doing just that Hell, if anything, it's better than letting it run backwards, which is what happens when they deisel. At least as a temporary measure, until you fix the real problem.

Mon Aug 11, 2003 7:40 pm

farmersdahtr wrote: To me nothing sounds more ghetto than a run-on engine. Dave

hah hah hah i agree with you there.

I was wondering earlier about stopping the engine like you were saying cause I accidently let go of the clutch when i was in gear and it stopped right away. But i'd imagine its no good, hell I dont mind lookin a little ghetto! :2gunfire:

Mon Aug 11, 2003 7:47 pm

order the choke. imagine the strain on all those parts when you just let out the clutch. come on guys.

Mon Aug 11, 2003 8:18 pm

I plan on it I am just poor right now.

Mon Aug 11, 2003 8:20 pm

If that choke is staying on, it would also be keeping your high idle cam activated. This would cause poor mileage, plus the increased idle RPM causes dieseling. Food for thought....

Mon Aug 11, 2003 8:23 pm

Now that you mentioned it, it has been getting bad gas mileage the last couple days.

Tue Aug 12, 2003 1:44 am

there seems to be some confusion here. The choke and the anti-dieseling devices are totally seperate. They are not the same thing. The carb on a 71 should have both electomagnetic devices. The anti-dieseling or fuel cuttoff valve is the only thing on the carb with a wire or a connector for a wire. If its not on the carb someone may have replaced it wirh a plug. If this is the case you have to look at the manual and see what is supposed to be there. You can test the valve by removing it, gounding the body and applying 12 volts at the terminal. The plunger should pull in. Take power away and it should spring out. If its not connected you can run a wire to it from the positive side of the coil. Thats actually how it worked stock anyways.

Tue Aug 12, 2003 1:46 am

What I meant to say was. Its the only thing on the carb other than the choke with an electrical wire or connection for one.

Tue Aug 12, 2003 11:00 am

Like I said in the post earlier just splice it in to the coil wire instead of running one back to the coil,(less wires save money and time, haha)

Sun Aug 17, 2003 8:15 am

Thanks for your help folks. But the only thing and simplest thing I didn't see mentioned here was gasoline. I bought some schwag gas on my way back from columbus cause I had too, so I have run about a tank of the 94 through it and The diesling is almost completely stopped.

I talked to a local VW mechanic. He's old school. And he said that he can't remember ever seeing a bad fuel cut-off valve. Or anti deisel device wichever you prefer to call it.

Sun Aug 17, 2003 9:08 am

NuggJugg wrote: Thanks for your help folks. But the only thing and simplest thing I didn't see mentioned here was gasoline. I bought some schwag gas on my way back from columbus cause I had too, so I have run about a tank of the 94 through it and The diesling is almost completely stopped.

I talked to a local VW mechanic. He's old school. And he said that he can't remember ever seeing a bad fuel cut-off valve. Or anti deisel device wichever you prefer to call it.

Bad gas or poor octane rating is definatnly a factor...

I can't imagine anyone "old school" never seeing a bad electric idle solenoid.... I have seen hundreds.... it is a common failure as the 71 and later 34 picts got older and after they started being made out side Germany.... I've seen "new' ones be bad in the box and or fail in short period of time. they are alos on the 30/31 replacement carbs...