Audi Repair: audi a4 2.8 30v quattro not starting, earth point, compression tester

Question
Hi, i recently bought a minor damaged 1999 Audi a4 2.8 30v v6 quattro, the damage was to the front and only needed a bumper and rad, as i work in body repair this wasn't a problem
however i have never had the car running, i have put fresh water, oil and oil filter in it and have good spark and there seem to be getting fuel to it,
it had remained unused for 2 months before i got it due to a damaged rad,
any ideas?

many thanks Kevin

Answer
Hi Kevin,

Basically an engine needs 3 things to start, these are.. Ignition, Fuel and Compression, if either of these are missing then the engine will not start,

Start off with the Ignition system, Remove the ignition leads and connect a spark plug to it then place the plug body on an earth point like on a metal part of the engine, then have some body crank the engine while you watch for a good strong spark, you should be able to hear it as well as see it.. do this to all the leads to make sure that they are all firing,

Next move onto the Compression, you will need a compression tester for this, check that the cylinders register about the same pressures,

After that move onto the fuel system, start off with the fuel pump, switch on the ignition and listen carefully at the tank system, you should hear a sight hum for a few seconds then it should shut off, then proceed to the pipe that connects to the fuel rail, disconnect it and then have some body crank the engine,you should see fuel coming out of it with pressure,(working in a workshop I'll assume you will take all necessary precautions when working with fuel)If all is ok up to this point then you will have to check that the fuel is actually getting into  the engine, to do this remove the fuel rail as a whole unit with the fuel pipe connected then have some body crank the engine while you watch the injectors, they should fire sequentially.

Also note that if the fuel tank is empty then the fuel pump cuts off as a safety to prevent over heating and thus damage to the pump which relies on the circulating fuel for cooling.

SO basically find out what is missing and rectify it as necessary.

Also on a personal note I'd start off with the fuel system as in my experience when vehicles are left standing for long periods sometimes the fuel pump jams and needs replacement.