impossibly lean running CA SC
 

Late 2007 I purchased a 76000 miles California 1980 SC on eBay, and had it freighted to Houston. Then last summer I took out 2 weeks vacation and came over from across the Atlantic, picked up the car and drove it to a friends place in Maryland. On arrival in Houston I spent a couple of days getting it to run, getting temporary plates, replacing injectors and a bad fuel accumulator. The throttle linkage was maladjusted giving only 3/4 opening of the butterfly, and it ran on 5 cylinders because of a spark plug connection. My first ride ever in a Porsche was less then impressive wrt power ! Over the following 2 weeks I did back roads from Houston to Maryland, covering approx 2400 miles in 2 weeks, and I am a very happy owner. My plan is to keep the car in the US for a couple of years for vacations, and then ship it to Norway.

One thing I didn't manage to resolve over my 2 weeks was the impossibly lean running of the engine. At cruising speed it had a distinct lean surge, and the exhaust was white. At load it had way less power than I would have expected, and I believe this was caused by too lean mixture. The problem was alleviated by disconnecting the O2 sensor but still it is pretty lame power wise. Now I have read up on how to adjust idle mixture and I will do that on my next visit, as well as installing the new SSI's and the Carerra tensioners.

my question to the forum is to what degree does adjusting the idle mixture (with the long 3 mm allen wrench) help on the under-load mixture ? I would think not much .... ?

How can I get the injection set up properly (given it is all working)http://forums.pelicanparts.com/uploa...1236288791.jpg

On my 82 (O2 sensor disconnected) if I richen my idle mixture it will result in a richer mixture under load too. You can verify by running tests with an AFR meter such as a LM2.

Currently I am running at 3.5% CO - somewhere around 13.2 ARR at idle.

How lean are you running and what did you use to determine your AFR?

didn't measure AFR. I decided it must be running lean based on color in tailpipe (dry white) and typical lean surging at cruising load and poor power under load. Will bring diagnostic tools next time I get to the car. I will try adjusting and see how it works, but I really would have liked to convert to EFI, and I guess I am almost just looking for an excuse to get something I can fiddle with. The bitz racing set up looks very good. Something drastic must be done to restore power

If you don't have an AF meter you can try a couple of things:

1 Turn the screw in 1/8 turn increments clockwise until, when warmed up and idling, you rev the engine and quickly get off the throttle, and it wants to drop down below idle speed before returning back. Then back off the screw about 1/16 turn. The revs should rise and then drop (with a slight pause if your decel valve is working) back to idle speed. On my car this gets me to approx 3.5% or about 13.2 AFR.

2 Or try searching Pelican "Souk". He has a technique called the "Push pull method" of setting the mixture in the field by working the sensor plate.