Misfire 945 1997 230FT

[Laird Scooby]

Originally Posted by jlawler

Spare is a new one. Whenever I've changed one I always get another one (just in case). I just never did it with the CPS as that wasn't that old. For some reason the ones I've got from Parts For Volvo's never seem to last more than a few years. The needle starts to drop off the midpoint when driving and I know that I have to change it.

Yes lower hose has the heater valve (with the vacuum pipe connection) in the middle. The other end runs to the connection under No. 4 cylinder intake manifold.

Sadly these days thermostats don't seem to last like they used to. I've taken to changing mine every 4 years, normally at the coolant change time. I also do a full flush including reverse flush at the same time.

The interim change just gets a basic reverse flush without flushing agent and that seems to work very well for me.

Heater hoses are connected correctly to the matrix from the sound of it.

[jlawler]

I got the thermostat changed and all good. Up to temperature in about 2.5-3 miles.
Heat still poor though. Does the vacuum controlled valve adjust the flow through the heater? Is it possible to test it.

Thanks

[Laird Scooby]

Originally Posted by jlawler

I got the thermostat changed and all good. Up to temperature in about 2.5-3 miles.
Heat still poor though. Does the vacuum controlled valve adjust the flow through the heater? Is it possible to test it.

Thanks

To answer your queries in order, 2.5-3 miles isn't really long enough to get everything up to temperature this weather, despite what the temp guage says.

Try swapping the hoses on the stubs on the bulkhead and see if you get an improvement.

The vacuum valve doesn't adjust the flow, it's either open or closed. With vacuum it's closed, without vacuum it's open.

Where have you set the temperature dial on the Climate Control?

[jlawler]

I think I found the source of my heater problem.
While poking around at another niggly issue I found this loose.
It's the hose from the heater control valve that goes up over towards the drivers side of the car.
Where should this end go as I can't see anything obvious?

[Laird Scooby]

Originally Posted by jlawler

I think I found the source of my heater problem.
While poking around at another niggly issue I found this loose.
It's the hose from the heater control valve that goes up over towards the drivers side of the car.
Where should this end go as I can't see anything obvious?

Should go to the left of the car and enter the back of the heater box via the bulkhead near the reciever dryer. That's the ehater control valve, means you have full flow through the matirx even when set to cold becaue it's not getting the vacuum signal from the heater controls.

[jlawler]

Thanks, I'll take a look. When you mean left I assume you mean passengers side rather than looking at the engine compartment from the front.

If you get a chance I'd really appreciate a picture.

[Laird Scooby]

Originally Posted by jlawler

Thanks, I'll take a look. When you mean left I assume you mean passengers side rather than looking at the engine compartment from the front.

If you get a chance I'd really appreciate a picture.

Yes, i always quote sides as viewed from the drivers seat.



As viewed, the vac hose for the heater valve is to the left of the left hand NRV in the pic going downwards.

[jlawler]

So while I had the head off the car I found the other end of that broken heater control valve tube.
On my car (climate control) it runs to the right and enters through the bulkhead below the lower heater radiator pipe and goes through into the left hand side of the drivers footwell.
You'll see the broken pipe in the photo just below my middle finger.

There are two other tubes with it and a wire in a glass sheath.

I managed to splice it with some softer hose over the two ends and then sealed with cable ties (well stuck).