Need Help

[shellib 0]

I recently purchased a 1990 Corrado that is experiencing some electrical issue. It has 62,000 miles. After leaving it parked for a few days I came out to find the battery dead. Assuming that the battery was old (the car had been in storage for most of it's life) I installed a new battery. It drove fine, however, if I am parked for more than 2-3 days the car will not start.

 

Last night I went out to start it. When I got in the car the interior lights came on and the car turned over 2-3 times before the battery died. I tried a second time and got nothing. I pulled the key out and went to get a battery booster. When I returned I noticed a sound coming from the left rear quarter panel area. It was a click sound which reminded me of a pump actuating. It went on and off at a regular rate. I then put the battery booster on and the car immediately started up.

 

I drove around for about ten minutes and then turned the car off. It started right back up with plenty of power.

 

It is a new battery and I have checked that it still shows as OK. The terminals are very clean and tightly attached. The alternator is clearly working as it will charge the battery plenty as long as I drive it regularly. I know that there must be a short/electrical leak somewhere but I don't have any ideas.

 

All the lights are definitely off when I park it and there are no accessories plug into the cigarette lighter/power outlet. The sound I heard near the left rear quarter panel was something I had not noticed before (may have been there before but I didn't notice) and I thought maybe it could be a fuel pump actuating and draining the battery.

 

Other than the battery being dead the car runs like a dream with no issues. Does anyone have advice on what this could be?

[DanVW 0]

I know you said all the lights are off but... Did you double check the boot light? This is what killed my battery recently and in fact it's still disconnected.

[domwells27 0]

Left side looking from which direction, drivers side or passenger side? Could be the central locking pump if drivers side. Have you got a multimeter?

 

Your best bet is to disconnect the negative lead of the battery, then attach a multimeter between the negative terminal and the negative lead. Turn everything off, keys out of the ignition etc, then measure the current drain. With everything off it should be very small (

 

I have this on my car at the moment, and found it was fuse 21 which controls the interioir lights and MFI. Haven't isolated the exact cause so have just been running without the fuse for now.