If it's really what you've described, fuel starvation, you gotta check the fuel pump. Because it sits in a little barrel inside the tank, which is always filled with fuel exactly to avoid fuel starvation when there's not much fuel in the tank and you ride on inclined surfaces. And the barrel has a little plug on the bottom, if that fell off you might have a problem. To check if that is the case without taking the fuel pump out you can fill up the tank or at least above half. And ride the car doing that left turn you associated with fuel starvation. On full up tank there wouldn't be a starvation.
I don't think it is an electrical problem, as it only happens when the tank is half full or less. If it were an electrical issue it would still happen even with a full tank. The less fuel there is in the tank, the more often it happens.
At half a tank, it only happens on sharp left turns. On a quarter of a tank, it happens on more gentle left turns.
Or is it a modern squat lump with multiple cables?
Modern type. I don't think it's misfiring selectively as it's losing ALL power, rather than juddering along like it was losing one or two cylinders sporadically. It feels like I've just taken my foot completely off the accelerator when it happens, and it takes a second for the power to kick back in after straightening up. Sometimes, if it's a short and sharp left turn, the power doesn't cut out until after you're going straight again, as it takes a little bit longer for the fuel to slosh away from the pump than it takes to go round the corner (I assume). These drops in power can last quite a long time, if you're going round a long left hander, or can only last for half a second if it's just a quick left.
Then check the main battery earth cable, and the engine mountings. The cables can corrode internally, becoming brittle and breaking connection. As you turn left, if the engine moves on its mounts, it can break this connection.
I may have poor electrical connections, as I always have a dim battery warning light on the dash despite good voltage. Battery neg cable already tested for this, no luck. The engine mountings are old and probably worn out, but I don't think they are causing this again because it only happens on lower fuel levels.
Might have to take the fuel pump out of the tank and check its condition. The plastic fuel tank should not have created any rust debris, but you might find brown good from the car standing for some time in its past. The pickup filter might have fallen off.
It was in a shed for 15 years until I bought it in November... could be a gummed up filter? Strange it only happens when turning left though, you'd think a bad filter would take effect all the time.
Pump comes out from under the rear seat, but the plastic retainer can be well stuck, so prepare for some special language, and the edges of the aperture under the seat are sharp, so blood might be spilt.
I've been under the seats many a time, annoyingly, trying to resolve a leak from the fuel sender seal so I'm very familiar with sliced knuckles in that metal opening! My feeling is that it must be related to the fuel pump, and that the mechanism for keeping some fuel at the pump despite any manoeuvre you pull off has failed.
My diagnosis is as follows:
- Car loses all power, not just a misfire, therefore must be related to fuel supply to all four cylinders.
- Only happens on low fuel level, so must be related to the tank.
- Only happens when turning left, so fuel pump/filters should be functioning normally.
It does take a few seconds for the car to start from cold which could be a sign of a weak pump, but again I don't think this would show itself ONLY on left turns.
If there are any other possible causes, I'd appreciate your thoughts on them. Hopefully I've explained everything clearly enough!
