₦airaland Forum

The reason behind this is a leakage (loss of pressure) in the engine. The revving of the engine is from the brain box, trying to stabilise the engine pressure and that's why it takes a little while before it normalises. This leakage(s) usually occurs between the engine block and the part where the injector joins the engine. You can find out exactly where it's leaking by simply pouring water (in small quantities) in this area while the engine is on. Once u notice a change in the sound of the engine while doing this, note the spot and work on it. It is usually an old or broken "gasket" that you'd have to deal with.