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Thu May 22, 2003 2:59 pm

I need advice. I recently purchased a '71 super beetle. He has a petronix electric ignition, and a 34 pict carb. There is no power at take off when the motor is warm. There is some backfiring too. when the motor first starts i can drive 55 easy, but when it warms up, i'm lucky to get to 35! HELP Pleeze!

Thu May 22, 2003 6:59 pm

I assume you mean the petronix module that fits on the distributor where the points would go? I had a similar problem with my bug a few years ago, then it finally died altogether. I was running one of those petronix "ignitor" drop in points modules. So that maybe your problem. If your car is running well when it is cold, but poorly when it is hot, you may have a sticking choke. Or your car may be running too lean, and running well only when it is running richer when the choke is on. I would check to make sure the carb is adjusted/jetted properly and is clean. Also make sure that it is bolted to the manifold properly and not leaking air. Check the small rubber boots that connect the intake manifold to the cylinder head end castings. Check to make sure they are on tight and not cracked or split. If you haven't already done so, you may want to do a complete tune up. New spark plugs, valve adjustment, new spark plug wires, distributor cap and rotor.

It is also possible that you have a bad distributor. Check the timing with a stroboscopic timing light. If the timing mark is bouncing all over, then your distributor is probably worn out, and that would also cause the symptoms your describing. Check the fuelpump pressure as well. As you could have a bum fuel pump, or even a really clogged fuel filter.

I know it sounds like alot to check, but if you are familiar with VW's you are looking at about 1-2 hours of troubleshooting time. If you are not familiar with VW's, then you may want to take it too a reputable shop that works on aircooled VW's.

Good luck!

Thu May 22, 2003 7:03 pm

A couple more ideas, check your airfilter and make sure it is not dirty and that it is hooked up properly. Also, the intake manifold end castings that connect to the cylinder head of the engine (silver tube like things near the spark plugs) can come loose over time. Make sure these are on tight, and with the engine running spray some carb cleaner around them and see if it makes the engine speed jump. If it does, then they are leaking vacuum.

Thu May 22, 2003 8:30 pm

Get rid of the electronic ignition motherfication junk. If it isn't a problem now, it will be down the road. Then, check everything that Aircooled said to check. Then, MAKE SURE YOUR CHOKE IS OPENING. If you test the manifold boots with carb cleaner, make sure you have a fire extinguisher handy, and make sure it works. Carb cleaner around ignition parts can turn into shock and awe pretty quick. Make sure your valves are adjusted right, too. Too tight can run decent with the engine cold and lose power hot.