1982 911sc no start issue

[tg3087]

I'm having trouble getting the car to start. I drove it into the shop and replaced the Alternator. After everything was put back together the car wouldn't start. I double checked all wires and all looks good. I started looking at the wiring schematics and noticed the CDI box controlled the firing for the engine. I sent it off and they confirmed it was faulty and rebuilt it. I reinstalled it and still not starting. This is a German spec car and sometimes during the 90's someone rewired it to run a GAT-Tronic module (which the company went out of business in the late 90's) for the emissions. They have the coil positive wire plus 7 other wires running to the module. I took the module apart and can tell it's burned out. The OXS module under the passenger seat had been removed also when the GAT-TRONIC was installed. When I rewired things back to where they belong I still have the frequency valve and Ox sensor without a place to wire into. I installed the coil positive wire back to the correct terminal in the CDI box but still not getting any fire to the spark plugs.

Any advice to getting this car back running will be much appreciated. I am totally lost on what to check now. Unless my CDI box is faulty again.

[boyt911sc]

TG,

This is your first post, as a protocol, new member posts some pictures of their car. Ignore this protocol and you will be ignored. Welcome to the forum.

Could you post a picture showing your WUR? This would be the area between intake runners #1 & #2. BTW, who rebuilt your CDI? Thanks.

Tony

[tg3087]

Yes this is my first post and don't see where to attach photos to this thread.

ecudoctors.com did the CDI rebuild

[tg3087]

[tg3087]

[tg3087]

I'm considering sending back the CDI to have it rechecked.

[timmy2]

What color is your coil?

[manbridge 74]

Find a factory wire diagram and re-configure it correctly.

Also make sure all parts are correct for 1982 via PET, Porsche's parts catalog.

All the hacky stuff is the cause of your trouble...

[SC-targa]

German spec cars do not have a frequency valve.

What is the engine type? Should be a number on the motor, such as 930/16.

[boyt911sc]

Tg,

Let's begin to identify your engine type and CIS components. Is it a US or ROW spec car?

Engine number
Engine type
WUR
FD
AAR
AFM

Look at the Bosch ID numbers for these parts and post them. Thanks.

Tony

[mysocal911]

Originally Posted by tg3087

I started looking at the wiring schematics and noticed the CDI box controlled the firing for the engine. I sent it off and they confirmed it was faulty and rebuilt it. I reinstalled it and still not starting.

Typical! Their response: "Your CDI box would have needed to be rebuilt in the future anyway."

Originally Posted by tg3087

Any advice to getting this car back running will be much appreciated. I am totally lost on what to check now. Unless my CDI box is faulty again.

Most likely the CDI box was originally OK. You need to focus on getting a spark:

1. Using a test-light, check that power (12 volts) is getting to CDI unit - center pin (#15)
and that the CDI is buzzing with power.
2. Using an ohmmeter check for about 600 ohms from the distributor pickup
(pin #7 to the nearby pin #31) and about 1.0 volts AC while cranking from the same pins.
3. Check the connections (pins A & 31) from the CDI box to the coil. Make sure the coil is black
and not silver/gold.
4. Remove the center wire from the coil and place it about 10mm from any engine metal
while cranking.

Remember:

Originally Posted by tg3087

I drove it into the shop and replaced the Alternator. After everything was put back together the car wouldn't start.

[vintagecarlover]

Subd