Idle stabilisation control unit
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- REGGAJ
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Idle stabilisation control unit
Hi, i have a 1985 1.9injection GW engine code and im after an idle control unit ( The wee black box that sits behind offside light cluster). The code on my unit is 251 907 393. Having done a bit of research i have found a few for sale but they either have a letter B or D after the numbers. Could anyone tell me what the correct one is i need for my engine Thanks.

- icosahedron
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Re: Idle stabilisation control unit
The idle stabilisation control unit is an analogue circuit that outputs a pulse width modulated signal to the idle control valve. Its function is to maintain a constant idle speed while the engine is warming up and when power steering and air conditioning kicks in. As far as I can ascertain this does not make the unit engine specific and that the variations indicate circuit revisions.
I recently discovered a dry joint in mine (Rev. A) and got a spare for the road (Rev. C). Both work fine with my DJ engine with only a slight idle speed adjustment required. I investigated the different variations before buying the spare, translated information from a German forum and learnt of someone running a revision D on his DJ without problems.
However, some maintain that A and C is for DJ and B and D for MV but they do not provide a reason for this. Sensors for ISCU on DJ and MV are the same.
I recently discovered a dry joint in mine (Rev. A) and got a spare for the road (Rev. C). Both work fine with my DJ engine with only a slight idle speed adjustment required. I investigated the different variations before buying the spare, translated information from a German forum and learnt of someone running a revision D on his DJ without problems.
However, some maintain that A and C is for DJ and B and D for MV but they do not provide a reason for this. Sensors for ISCU on DJ and MV are the same.
- REGGAJ
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Re: Idle stabilisation control unit
Great thanks for that, iv seen loads of info on 2.1 injection but nothing really definitave regarding the 1.9 gw engine code, ah well the search goes on 


- Hacksawbob
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Re: Idle stabilisation control unit
Wiki'd

icosahedron wrote:The idle stabilisation control unit is an analogue circuit that outputs a pulse width modulated signal to the idle control valve. Its function is to maintain a constant idle speed while the engine is warming up and when power steering and air conditioning kicks in. As far as I can ascertain this does not make the unit engine specific and that the variations indicate circuit revisions.
I recently discovered a dry joint in mine (Rev. A) and got a spare for the road (Rev. C). Both work fine with my DJ engine with only a slight idle speed adjustment required. I investigated the different variations before buying the spare, translated information from a German forum and learnt of someone running a revision D on his DJ without problems.
However, some maintain that A and C is for DJ and B and D for MV but they do not provide a reason for this. Sensors for ISCU on DJ and MV are the same.
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- Hacksawbob
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Re: Idle stabilisation control unit
thers a bit of info on BY
http://www.brick-yard.co.uk/VehicleSpec ... GWdata.htm" onclick="window.open(this.href);return false;
http://www.brick-yard.co.uk/VehicleSpec ... GWdata.htm" onclick="window.open(this.href);return false;
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- icosahedron
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Re: Idle stabilisation control unit
The following sensors connect to the ISCU:
1. Temp II sensor.
2. Throttle switch.
3. Ignition Hall effect sensor.
4. Power steering pressure switch.
5. Aircon compressor clutch.
Nothing engine specific unless the GW temp II sensor is unique.
1. Temp II sensor.
2. Throttle switch.
3. Ignition Hall effect sensor.
4. Power steering pressure switch.
5. Aircon compressor clutch.
Nothing engine specific unless the GW temp II sensor is unique.
- REGGAJ
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Re: Idle stabilisation control unit
Yeah thanks for that, im still hoping someone might know the specific code req for my engine type.
