Technical Crank no start & blowing fuse

[nullogik]

Hi,

I wonder if someone could help me save our 1993 Cinquecento SX which we've had for 15 years.

About two weeks ago it cut out and wouldn't re-start immediately. About half an hour later it started and has been running fine since. Until yesterday when it did the same just as I had finished parking up. When it cut out it did so "cleanly" i.e. it didn't misfire/jerk/run rough for a second or two before cutting out. It was as if someone had turned the car off.

When you turn the key the fuel pump does prime and the dashboard lights come on. The car cranks as usual but won't "catch". I pulled the leads out and there is no spark during cranking.

A Fiat mechanic says it keeps blowing a "main fuse" but I haven't been able to find out from him exactly which one he was talking about. He then said he has swapped out relays and it hasn't helped and has run out of ideas. I'm not entirely convinced by his diagnosis but to be fair I haven't seen the blown fuse.

Any suggestions would be greatly appreciated.

 

[Jordan Strathon]

That's very similar to what happened to my MG when the battery connector came loose and ended up causing a surge blowing a fuse a bit later and then blowing twice more when replaced. I would think on yours there'll be a short somewhere that's causing it to surge and blow.

 

[nullogik]

My mechanic has diagnosed a faulty fuel pump that was shorting out. He's fitted a new one and the car is now running. At my insistence a new crank sensor has also been fitted as I gather from old threads that they are a weak point on these cars (and mine is on its original one).