TM___

Hi guys,

1984 Euro S(2) twin distributor.

Quick question: can you turn the MAF screw (the one used for adjusting CO) too far?
My (JDS revised) MAF reads 0.3 Ohm between pins 3-6, CO remains at 5% (dropped from 8%).
Now I switched ECU's and it won't start. Tried turning the screw back up to the 380 Ohm starting point, but the resistance reading does not change.

Have turned at least 50 turns clockwise, and it is still at 0.3 Ohm.
Is it possible the screw was turned too far CCW s.t. it released from the actual internals, and now it does nothing anymore?

Or am I doing something wrong?

PorKen

Try 4 and 6.

The pot is turned by a clutched-like spring thing so it should not be able to damage the pot, AFAIK.

TM___

It's now back in the car. I did check the other pins each with 3 and each with 6 and on some I got the 4.1 Ohm reading, but don't remember which exactly.

I contacted JDS Porsche and they can check it. That spring could be broken, or the pot itself.
Let's see how annoying shipping to/from the UK has gotten since brexit.

9two8

[QUOTE=TM___;

Let's see how annoying shipping to/from the UK has gotten since brexit.[/QUOTE]

Probably as annoying as it is from Europe to the UK !!

​​​​​​Ken
80 928S
5 Speed
UK

TM___

Europe > UK was pretty quick. I've posted the package last Wednesday and it arrived on Monday morning.
Let's see how fast it gets back here!

The MAF has been repaired (potentiometer was broken).

John Speake

Yes, it is possible to damage the pot if it is repeatedley turned against the end of track. If the CO stops changing when trying to set idle CO, don't turn any further.