vwrx running problem?

BlackCosmos · Padawan Joined: 01 Jun 2009 Posts: 94 Location: essex

I have an early wrx fitted in a t25,since being colder weather the cooling fans run as soon as its running..havnt driven it like this..any ideas??[/i]

james72 · Posted: Wed Dec 29, 2010 9:21 pm Post subject:

Maybe the temp sensor ? if it's shagged then the ecu will switch the fan on just in case. Got any error codes?
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1989 VW Magnum Multivan EZ30

ElusiveStranger · Posted: Thu Dec 30, 2010 3:41 am Post subject:

If it's as soon as you turn it on it'll be a temp sensor fault or the wiring's got a break in it leading to the ecu. The fail mode is to run the fan.
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'78 Bay, 2 litre 091 box, EJ20 NA & the ashtray's on the 'right' side.
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BlackCosmos · Padawan Joined: 01 Jun 2009 Posts: 94 Location: essex

The temp gauge works fine,take it means sender ok..did fault check and coolant sensor came up..its also hard to start..takes a while to fire??[list=][/list]

james72 · Posted: Thu Dec 30, 2010 7:13 pm Post subject:

The temp/coolant sensor talks to the ecu, the sender which is next to it, on the coolant manifold controls the gauge. Replace the sensor not the sender

the sensor is the bigger one 17mm iirc
_________________
1989 VW Magnum Multivan EZ30

ElusiveStranger · Posted: Fri Dec 31, 2010 3:03 am Post subject:

The temp sensor I mentioned is the one going to the ECU, not the gauge.

If the sensor (twin pin, usually Brown plastic) goes open circuit (or is it closed on fail) causes the ECU to turn on the fans. That's the "fail safe" mode.

"Takes time to fire". Sounds like you haven't got the cold start wire connected to the solenoid.
_________________
The advice you receive on here is worth the paper it's written on.
Your experiences are worth shed loads to others, including the f'ups - live and learn.
Wouldn't YOU rather learn by someone else's mistakes? So would they.

'78 Bay, 2 litre 091 box, EJ20 NA & the ashtray's on the 'right' side.
I don't lean forward for hills any more Grin

Bugger, missed out on "Live fast, die young"

BlackCosmos · Padawan Joined: 01 Jun 2009 Posts: 94 Location: essex

Right hung another sensor on,but still the same...it ran fine last winter. .wheres cold start valve? I left ecu disconnected overnight. .I,ll check codes again..

BlackCosmos · Padawan Joined: 01 Jun 2009 Posts: 94 Location: essex

quick update..removed all power from ecu for 36hrs,reconnected and bingo..seems fine..started up first crank and no cooling fans running..hope to use it tomoz..thanks for advice..happy new year!!