SC engine/injection problems?

[Wout_RS]

Hi all!

I'm new here, and since 3 months the happy owner of my first porsche.
It's a 1980 SC coupe, deliverd originally in the USA. Now I'm to owner and I'm located in Europe.

But i have some questions.

I've got some problems starting the car, benzine pump is running, but it starts and dies after a couple of seconds. After a few tries mostly the engine starts to run and to keep it up you have to keep the throttle slightly down a couple of minutes.
Then when i go out for a drive, when pushing the throttle it produces constant backfires.

I think the problem is the K-tronic. But what do you guys think?
Should I have a look at other possibilities before looking at the K-tronic?


I hope someone can help me!

Regards!

Wout

[Flat6pac]

Check your timing and timing advance
There is a VW relay under the seat available at auto stores for a few dollars, change it out. If relay is defective, it feels like a WUR gone bad.
Check pop off valve and make sure the rubber seal is in place.
Some things to start with.
Backfiring through the injection is usually a lean condition.
Unplug the oxygen sensor because it will override any changes made in the injection.
Bruce

[Wout_RS]

Thnx!

What do you mean with the VW relay under the seat? Is it in the DME box you mean?

The pop off valve seems good, is there a special rubber seal for it?

DO you mean, when it doesn't want to start, unplug the oxygen sensor and try to start?
And do you plug it back when it's running?

[Flat6pac]

The VW relay is under the passenger seat next to the computer box
There is a rubber seal that's part of the pop off valve and they're known to come off.
Unplug the ox sensor to change enrichment and idle speeds.
Bruce