912E quit running

[Mountainman]

Hi everyone, hopeing for a little help.
Was on my way home yesterday after a 200 mile cruise to see my mother, accelerating up a steep slope, 4000 rpm with all gauges normal when the engine just quit. No stumbling, hesitation or warning. Got it off to the side, tried to re-start 3 times but no luck and the battery was about dead too. No smell of raw gas, appeared to have spark, fuel tank half full.
Had it towed home and put the battery on a charger for 20 minutes. The engine turned over immediately after the battery charge ? The battery is admittedly old but has not given any problems to this date.
Is it possible that the battery or the voltage regulator allowed the system voltage to drop too low to continue operating and just shut down ? Alternator is fairly new with a good belt.
Since it re-started after charging I am assuming the fuel relay and pump might be OK, at the very least they were operational. Fuel filter old, I will replace it along with the battery. The fuel pump is always quiet and have never been able to hear it run so listening for it to turn on with the ignition wasn't a viable option at the moment.
Thoughts ? Similar experience ?

[csapp05]

Several things come to my mind, the fuel injection does pull quite a few amps when running, so a weak battery could be overwhelmed especially if the car sits awhile. Also, check all grounds, check harness plug on the lower left fuse panel, clean all contacts, start car and check the voltage at the battery, should see at least 12-13v when idling. Turn on the high beams, fan, a/c if you got it and check again to see if the alternator can keep up with demand.
Let us know what you find!

[Mountainman]

Thank you for responding. Shall take that advice and give it a try. Starting with a new battery and fuel filter too. Pretty busy at the moment but will get back when I have some more of this figured out.

The ECU of L-Jetronic injection system is quite sensitive. Take care with jump starting the engine or using an exhausted battery.

Apart from a charged battery, starting the engine was also done with a cold engine. I guess you didn't try that before during your trip. It could be a temperature related problem then. When the engine started with the charged battery, did you run it to operating temp? Did it restart then?

Otto

[Mountainman]

Thanks Otto. I drove roughly 100 miles and stopped to fill up with gas. No restart issue. Drove on to my mom's house and parked. Re-started 3 hrs later but now that I think about it more it was a bit of a slow start ( like a low battery ).
Today I'll install the new filter but will check the fuel pump before re-connecting the lines.
If the pump works I'll move on to the new battery as well. If not I'll check the realyas and pump. I'll keep you posted, thanks again - Dennis

Dennis,

PM sent.

Otto

[bugmeat]

Nice car - I love that color. More photos please!

[monovich]

I hate to rubberneck without contributing, but that is a gorgeous car. I love that color.

[Mountainman]

Thanks for the nice comments about the car color. It is Porsche "Nepal Orange". To the best of my knowledge it was only available on the 914 in 1975 and 1976.
I loved the color too so when I restored this 912E four years ago I decided to repaint it in orange. It was originally black.

[andybullen]

Nepal Orange.... love that color!