After some confusion over the use of IACs with Pers soft and firmware, I had a closer look at the three Bosch IAC valves I have on my workbench, all from scrap.
All three operate differently and there are also discrepancies between Pers data and those I found when checking against what I got. Here is my little contribution:
Bosch 0 280 140 505 (Also VW Audi 034 133 455):
- Shape: outlet at 90 deg to inlet
- Total length: 141 mm
- Position unpowered: less than 1/4 open, spring centering
- Connections: Terminals marked 1,2,3 (looking at connector with central notch on top), when connected as per Pers diagram(1: +12V; 2: grd via 10 ohm; 3: to MS) the valve will be open with 3 open, closed when 3 is at 12V.
- This valve will NOT close when connecting 3 to grd, as it should when connected to MS Idle out. This is why it will always be open when hooked to MS. Played with other ways to hook it up, could not find one which worked.
Bosch 0 280 140 501
- Shape: outlet and inlet in-line
- Length: 107mm
- Position unpowered: indifferent, no spring
- Connections: terminals marked 3,4,5 (as above). with +12V connected to central terminal the valve will be either open or closed with either 3 or 5 conncted to grd.
Bosch 0280 140 516
- Shape: inlet at 90 deg to outlet, cast body
- Length: 124 mm
- Position unpowered: closed, spring loaded
- Connections: two pins. Will open when applying dc, nice linear response in the range 1 to 9V, 1A at 9V (open)
on this site: IdleControl
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