Climate Control And Engine Management

Hi, we had a `98 CT Turbo with AC in the other day and I noticed the heater fan started blowing straight away even though the temp was set at 30 and the engine was stone cold. Just wondered what could cause this as our 25 estate without AC climate doesn`t blow until the engine warms slightly. I`m guessing a temperature sensor somewhere is reading wrong.

Also the car has an engine management problem where the K light flashes up now and then. The fault code reads boost control circuit. Has anyone else experienced this and if so what cured it? It doesn`t seem to cause any problems just anoying the owner.

Boost control could be sticky waste gate but i haven't played with my turbo enough to know the ins and outs of the management, or induction systems yet.
The heater matrix feed pipes on the left of the the drivers foot well have a sensor clamped to the flow to the matrix, this could be dead, telling the control system that the coolant is hot all the time, its somewhere to start anyway and easy to get at.

D

where exactly is that sensor, never seen it, its now a challenge to find it.......

I think the sensor dean is on about is clipped to the alloy heater pipes next to the steering column. I`ll have to look one out and give it a try .
Cheers

Thats the one

D