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[AGD931]

Changed the boost switch yesterday (930 606 101 00) and whilst removing the old one, found traces of oil on the threads of the charge tube. Is this normal?

I also received a reply from a well known Porsche specialist in England concerning my pinking problem (see below). They suggested flushing out the air pressure pipe that goes to the DITC. How do I do this? Apparently if this does not eliminate the pinking, they suggest fitting a DITC from a Carrera GT which has less advance. (Mega bucks and probably not even available).

Would appreciate some help here

Thanks
Arthur

REPLY RECEIVED
JZ Machtech: Pinking was a common problem on this model, even when the cars were fairly new.

Try removing the air pressure pipe from the ECU and flush it through. Oil collects at the bottom of this pipe and also in the pressure sensor inside the ECU. This renders the sensor less sensitive to pressure change, thus causing the ignition to stay advanced when it should be retarding

The so-called "rest of the world" specification of ignition ECU fitted to the 1982 924 models had less advance. Porsche superseded the pre-1981 ECU with the type used in a Carrera GT, part number 937 602 071 00. This has less advance: 31-35 degrees BTDC at1500rpm, compared to 35-39 degrees BTDC at 1500 rpm. So if cleaning the air pipe does not cure the problem, we suggest fitting the later ignition ECU.
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1981 931 S2
1990 E30 320i Cabrio
1979 Ford Capri Ghia

[924guy]

the oil recirc system will indeed leave "residue" in the intake system. the oil separator is supposed to "catch" most of it, but youll always have oil vapour that will pool and collect in spots throughout the intake system. i wouldnt worry about it too much, its design inherrant (look at the path "air" travels into the airbox , not only from the fresh air intake, but alos from the other tied in recirc systems, and itll make sense, sort of.) , unless there was a great deal of it anyhow.. .
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Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
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