My Volvo V40 1.9 Diesel 115 bhp, is drinking more fuel, accelerating less well and the engine is hesitating at around 2000 rpm. The car has a full service history, so what is the problem? Then I noticed this thing called an EGR valve, which Volvo neither service nor check.
Inspired by this excellent thread by Biotoxic I thought I would clean my EGR valve. All went well. The solenoid separated from the EGR valve. But the EGR valve was stuck fast in the inlet manifold.
So, lots of penetrating fluid, a wooden stick and a rubber hammer were tried, with no reward.
Then a cold chisel and steel hammer was tried. The EGR valve was bruised but survived unmoved.
I realised that less brute force and more brain power was necessary. I researched the idea of heating the manifold and made a bespoke tool to use as a drift.
I know nothing about the manifold's aluminium alloy, but realised that an oxyacetylene torch would not be good. I settled for a hot air gun (1800 Watt, 600 Centigrade).
My new tool was made from an old tyre lever and a M8 nut and bolt.
An appropriate weight hammer was selected
I applied the hot air to the manifold casting in the area of the EGR valve. After about 10 minutes the EGR area of the casting had reached 50 Centigrade. Then the new tool was engaged in the bolt holes of the EGR valve. A few light strikes with the hammer caused the first movement of the EGR valve. 10 minutes later it was out.
It was oily, sooty and black. I tried to clean it with kerosene, acetone, carburetor cleaner and a toothbrush. None were that helpful. More reading suggested that a ultrasonic bath would clean this valve. I prepared a cleaning solution from detergent 5 g, sodium hydroxide 5 g and water 1.5 l. Three sessions in the bath left only a brown varnish on the valve.
The valve was so clean it slid straight back into the manifold.