As mentioned in my Introduction thread, my 1996 Series 3 LS400 has started stalling randomly. It’s got 163K on the clock.
It usually stalls when slowing down from a high speed run, so mostly on Motorway Slip Roads or A Road roundabouts. Whether the exit has uphill or downhill Ramps make no difference as it has stalled on both. Usually all the dashboard lights begin to flicker before it actually stalls, though it normally keeps running until I am down to around 2mph or less. Sometimes it does cut-out at higher speed, usually if I am really breaking hard. I’ve just had a cut-out at around 20mph while going round a bend at the end of a dual carriageway slip road. Every time it happens, it restarts immediately, with normal tickover.
If the car doesn’t stall outright, then the Tickover gets progressively lower. I’m getting good at coasting to a stop with a tiny bit of throttle to just keep it alive. It doesn’t make any difference if put in a lower gear. If it stops without stalling then I can put it in neutral and use accelerator to give 1000rpm and keep it running. Same again, when it does finally stall, restarts immediately, with normal tickover.
If you press the aircon button, the tickover rises to compensate for the extra engine load, so it doesn’t usually stall. Hard braking on motorway sliproads can still stall the engine with the aircon on.
This doesn’t seem to be weather dependent (Hot/Cold, Wet/Dry)
Once the tickover starts to fall, it doesn’t recover back to normal until the engine is restarted. I could stop at several consecutive junctions with low tickover and the engine almost laboring, but the tickover only ever recovers when the engine is restarted.
If I just drive it around town, like I have today, then no problems, the tickover stays normal. It needs to have some kind of sustained 5 minute run at speed.
Any ideas? I don’t want to go to a garage with this problem as the car isn’t worth too much now and it’s going to be uneconomic to have it looked into on huge detail.