HELP! - Cars runs shortly then dies

Don't change the pump! If the carb bowl is full when it dies, then it is not a starvation problem.

Is it dying out on the hiway? Will it run if you keep the throttle wide open?

If it won't keep running even at full throttle, I'd rule out carb and vacuum leaks, etc.

That leaves spark. Check for spark as soon as it dies. You'll have to be quick.

Coils can be intermittent as they heat up. A loose terminal also possible. Points/condensor...less likely.

Ignition switch should not be overlooked. Put a 12V bulb on the Coil + terminal to ground. See if the bulb goes out when the engine dies.

Speedy Jim

A blocked fuel tank vent would leave fuel in the filter and lines.

I will assume a Beetle or Super or KG (1971-1974) Does fuel come out of the accelerate jet nozzle when you open the throttle? If so you are getting gas. ;-) I will assume you can't keep it running at all. Maybe it is flooding out?

It might be an ignition problem! How is the spark? Points can cause problems like what you are experiencing.

BTW I have seen people fill up their fuel tanks with diesel fuel! 8^o

later, dave (One out of many Daves)

Check the electrical connection to the choke. It might be stuck on.

Okay, I'll shut up now.

Could it be the choke is not opening after the car warms up? If the choke does not open after the car reaches operating temperature it will be much too rich, sometimes so rich that it will die. I'd get a Volt-Ohm Meter and check the resistive heater that heats the bi-metal spring that opens the choke. It is not uncommon to see these burn open. If the heater is o.k. then check and make sure it is getting 12 volts (or 6 volts in an unconverted pre-67).

I saw this symtoms caused by a condenser in the ignition circuit. bye....MIC

Thanks for your input...

I don't even think the car has a chance to warm up before it dies. I should time it, it only runs for about 2 minutes from a cold start.

This is all in my driveway.

I've tried one other cleaned out carb and it did the same thing. I will try another clean carb ( I have a totoal of 4). - and I have extra fuel pumps and coils - helps with quick troubleshooting

One of the reasons why I thought it is a fuel pump is because when I placed on my second clean carb ( float bowl empty) it took over 3x as long for the car to catch to start - as if the fuel in the bowl was not filling all that well. I will see if the same thing happens with my

3rd carb.

Again, once the car runs, and dies if I count to 5 sec, the car will run for about 2 sec.s, If I count to 30 seconds the car will run about

20 seconds. If I wait a minute after it dies, it will run for maybe a minute. Strange.

My points are 46 degrees dwell.

did not check the spark, again, when it runs, it runs pretty well.

I will try a few things, including checking voltages, spark, changing out the condenser. again, I loosened my gas cap a great deal, and still had the prob, so I n't think it is a venting issue. Thanks - and any other thoughts may help!

Yes, air is not getting back into the gas tank to replace the gas. I had this happen and it was the carbon fuel tank vapour collector "tank" that filters the air coming out of the vent. I just disconnected this to see if that was the problem. A good hint ; is to take the gas cap off after you have this problem and listen for the air gushing in. good luck,

>

UDPATE

OK spent the last 2 days working on the problem When I could get the car running ( it was rough) I checked for vacuum leaks via carb cleaner spray; as occasionally, the cars' rpm would increase then greatly decrease which is indicative of a vacuum leak, only sometimes when I would spray would there be a change in rpms, but was never sure if it was due to my spray or by chance the engine "straightening itself out" at that moment. An area that seem to respond ( right manifold arm going to head) did not respond on subsequent sprays, even when I drowned it in the spray. - because of this I was not confident it was a leak. So I replaced...

the carb, in case if there was a partial orifice block(?) - as adjustments to the carb would result in no change in rpms whereas the day before it did. With my new clean carb, the car would not run - again. - I put the old one on. I barely got it started; ran rough

I replaced the distributor - as I thought that iti is possible that the vacuum advance mechanism was becoming defective - I had this happen once to me; also it was suggested to me the condenser could be going. SO with another distrib, I added new points and condensor, put it in and started the car - ran a little rough. Points were slightly off, adjusted them, car would then not start. adjusted them again, and again, both times car would not start. Put the old distrib back in, car would not start (!??!). Waited a while and the car started.

I replaced the coil ( it was suggested this could be going bad) - though spark seemed to be a little weak in color, car would not start again,, repalced with another - car would not start. Put back the original, car would not start. Relieved gas line pressure ( which I doubted existed but anyway) by removing a line from the carb & reattached, car would not start. Checked for shorted wires especially to the distrib and other wires running behind the coil. Did not see anything. Car started but ran rough.

As I feel it is a fuel problem, I replaced the fuel pump ( I once had a pump go bad on me though it still could pump a bit of fuel). I hooked the new pump up backwards with respect to the hoses (after car ran then conked out ) - this pump was set to feed to the carb from the lower pipe - opposite from what I ever had before. switched hoses around. Car would not start. waited 5 minutes, car started, still ran rough - but I noticed something.

WIththe new pump the clear gas filter was 3/4 filled with gas ( usually just a little was filling the filter). but with all that gas, I noticed it looked cloudy. I thought then maybe I have a lot of water in my gas tank. I went to the auto store & bought dry-gas. Poured it in , waited 20 minutes for it to disperse in my tank and barely got the car started. I ran it around for about 15 minutes to get it hot, and now it is idle-ing in my driveway for the past 2 1/2 hours without conking out !!!- still runing a little rough, rpms consisatncy seems to be pretty good. I jsut want to try to get a lot of that gas out. I'm tired of working on it and it's dark. Tomorrow if it starts, I'll test again for vacuum leaks.

But I wonder if water in the gas can besides get a car to run rough, but cause idle problems and VARY RPM(?). I may have been looking for a mechanical problem when there was none to be found. Once I confirm no leaks tomorrow I'll feel better. Just have to get new gas in the tank.

Thanks so much for everyone's help!! Really do appreciate it - and it still may be needed!

Matt S

Well it sounds like you have discovered your problem. You have some vacuum leaks and need to start by examining the manifolds, those boots and the base of the carb. Do the manifold sections have any vacuum ports on them? If so then plug them and see if the engine idles.

You engine stays running longer when the choke forces more fuel down into the engine.

At least that is what I am thinking! ;-) later, dave (One out of many daves)

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