1.9 8v Gti Rally Car Not Running

[jerseypug 1]

a girl i know has started rallying a 1.9 gti and at the last rally the battery came loose and the positive terminal of the battery earthed out on the body work and the car stopped running. we are both doing a rally on saturday and i am helping organise and competing so dont have any time to have a look. from what i have been told the cables going to the techtronic relay all melted, these have been repaired and a new relay, coil, ign amp and dissy fitted. the car will start for a second or two then stop with what appears to be the injectors not opening. does anyone have any idea what it could be. it will be her second rally and it will be a shame if she cant compete

[brumster 135 1 Cars]

Ruling out anything on the sparking side as I'll assume that's all fine, short of a still-faulty tachy relay (it has been known!), my first thoughts are ECU, water temp sensor or crank sensor. Given what's happened to start all of this, the ECU is probably the prime candidate - if the tacky relay frazzled out and melted in just the wrong way I'm wondering if it's passed some damaging high current to the ECU, but I must confess I'm only guessing.

 

Presumably the fuel pump is working and the pressure is up ok if it starts initially. Sounds to me like the rail is getting pressurised during that initial 2 second priming feed from the tachy relay, but after that either the relay or the ECU is it not picking up on the crank signal and re-activating the pump maybe (hard to hear the pump maybe after it's just started but worth checking).

[jerseypug 1]

Ruling out anything on the sparking side as I'll assume that's all fine, short of a still-faulty tachy relay (it has been known!), my first thoughts are ECU, water temp sensor or crank sensor. Given what's happened to start all of this, the ECU is probably the prime candidate - if the tacky relay frazzled out and melted in just the wrong way I'm wondering if it's passed some damaging high current to the ECU, but I must confess I'm only guessing.

 

Presumably the fuel pump is working and the pressure is up ok if it starts initially. Sounds to me like the rail is getting pressurised during that initial 2 second priming feed from the tachy relay, but after that either the relay or the ECU is it not picking up on the crank signal and re-activating the pump maybe (hard to hear the pump maybe after it's just started but worth checking).

 

cheers for that, where is the crank signal taken from, i know the mi16 and gti6 have the sensor in the gearbox but havent seen one on the 8v apart from the diagnostic one that does not seem to do much. they have tried another ecu and there was no difference

cheers

tim

[mickie 3]

the alternating current probably just comes off the dizzy

[jerseypug 1]

the alternating current probably just comes off the dizzy

just seen the car, the signal comes off the dissy to let the relay know the engine is turning over. when the dissy lead was wiggled, the techtronic relay was clicking open and shut. they changed the dissy again and all seems well

[mickie 3]

nice one, i thought it would probably just be that