1998 Diesel Renault Megane Very Poor Starting

[billysmart]

PROBLEM
Very poor starting and very smokey when the engine starts

SOLUTION
Bad earth connection in engine bay. Open the bonnet and look high right in the engine bay you will see a black box about 7 inches long, 2 inches high about 2 inches deep with a couple of thick red cables and several thinner ones to it. This is your glow plug relay box. You switch the ignition on and this sends power to the solenoids/relays in there which completes the circuit and sends battery voltage direct to your heater plugs. The earth for this and I think several other systems can corrode which means you get very little or no power to heater plugs. To find this earth point, look at your fuel injection pump and look down about 12-18 inches and then 6-12 inches right. Underneath the thick black coolant pipes you will see a star bolt head. Wiggle the cable and you will probably break it as it will be badly corroded. This is the earthing point for your glow plugs.
I couldnt get mine out so a couple of pieces of oven wire connected to the cleaned up cable end and then to a gear box bolt made a great substitute.

SHORT TERM SOLUTION
Take the small screws out the bottom of the black relay box (the one that is at the back of the engine, on the bulk head and high right) and remove the lid. Use a piece of wood or insulted screwdriver to manually press the two copper plates together for about 20-30 seconds while your ignition is on (dont worry if you touch the copper bits, the only danger might be the plates get warm hence the wood or screwdriver). This is sending battery power to your heater plugs. You only need to do this when the engine is cold. As I know what I am doing (ex army mechanic) I let go of the switches and started the engine and then put it all back together as the longer you leave starting, the harder it becomes.