Strange Happening

Argeo · 08-20-2003, 04:53 AM

I wrote yesterday how my car would start after I replaced the ignition coil (wouldn't start before) but was idling at real low RPMS. Well last night I started up and it ran much better. One thing it did do was start and immediatly die a second later like the power was cut off. I restarted and it idled ok. I did tinker with the points the other day without a feeler guage. Does my problem sound like the points need to be adjusted? The car ran great three days ago. It died two days ago and my neighbor tried adjusting my points. That did not help. Well then I put a new ignition coil in the car started but ran poorly. Well as I mentioned above, last night it started and ran ok after the first shut down. Does it sound like my points need to be readjusted? Does anyone know where I can get braided wire? I replaced all my wiring coming off the CDS unit a while back and haven't had any problems but I should probably repair just incase.

Thanks in advance.

Rot 911 · 08-20-2003, 05:54 AM

What year is your 911? Before I went troubleshooting anywhere else I would definitely check the point gap because that was the last thing that anyone fooled with. Also make sure the coil is wired correctly and all the connections are tight including the plug wire from the coil to the distributor. Sounds to me like a loose wire somewhere or perhaps the screw that keeps the points gap set is loose and allows the gap to open and close erratically. If you don't know the gap find out what it is for your car, but any 911 will run decent with the gap set between .014"-.016". When you say "braided" wire, are you talking about the spark plug wires?

08-20-2003, 07:51 AM

Did you check your timing after adjusting the points? If you change the point gap, you change the timing. You could have sent the timing into a massive amount of retard, resulting in the slow idle. Conversely, you could have advanced it so much that it wouldn't start.

The CDS system is inherently tolerant of dwell, but the spec is, I believe, 38 degrees plus or minus 2. You'll never get that precise with a feeler gauge, you need a dwell meter. Regardless, check your timing first.

Regards,
Ed Cavalier
77 Targa

Argeo · 08-20-2003, 07:58 AM

Thanks guys. I am sorry, braided wire probably wasn't the right term. I meant that silver mesh you find around some of the wires coming off the CDS unit to prevent some type of interference or something .

Rot 911 · 08-20-2003, 08:00 AM

Quote:

Originally posted by ejc_77_Targa
Did you check your timing after adjusting the points? If you change the point gap, you change the timing. You could have sent the timing into a massive amount of retard, resulting in the slow idle. Conversely, you could have advanced it so much that it wouldn't start.

While I agree that changing the point gap can change the timing, I don't believe you can change the timing in the radical amounts you describe.

traderdan · 11-18-2003, 09:46 PM

hey what is that braided wire anyhow I'm doing my first porsche rebuild on a 72 T and I noticed it too. It looks like a ground that starts at the CDI box sheet metal connection and branches off to a ground near the coil that then connects to terminal 1 on the via a bown wire. The second leg of this braided wire appears to connect as a ground to the body of the distributor. I guess it would be a good idea to check and make sure this ground is solid as the points work as a switching ground with the CDI unit somehow. I know I'm a newbie at this stuff so any info would be helpful also.