davidknell
New Member
- Joined
- Jun 3, 2007
- Messages
- 8
I'm having a bit of a nightmare with the fuel pump in my SL55, which has been replaced twice in the last few years and less than 5,000 miles, and I'd be grateful for any insight that might help me get to the bottom of what's going on.
It was last replaced about a year ago, along with the pressure regulator and fuel filter. The tank was drained as well and the fuel discarded. The car stood for a while then, when I came to drive it, no fuel pressure. There was a thump from behind when the key's turned (way louder than the relay clicking) which appeared to come from the fuel pump. The car went back to the garage who'd done the work; by the time they got around to looking at it, the thing worked perfectly.
I'm now about 1500 miles down the road in less than a week, and the fault's recurring. Once one evening, and it had cleared itself by the morning. And, again, last night. I've had the following happen:
- turn key, thump from the back, no fuel pressure, no start
- turn key, pump runs, start engine, runs for a few seconds and dies - the pump doesn't start back up when the engine's started
- turn key, pump runs, engine starts, all well.
Once started and running, the car's fine.
I was wondering if this was the result of dicky wiring to the pump - maybe there was a voltage drop somewhere which meant it had trouble getting going when the engine wasn't running. A quick test of this theory by seeing what happened when I tried to jump-start the car (which gave me 14+V at the battery terminals); still just got a thump from the back and no fuel in the rail.
I have an iCarsoft widget which I'll stick on the thing shortly and see if it sheds any light. In the meantime, any and all advice, suggestions and commiserations gratefully received.
Thanks --
Dave
It was last replaced about a year ago, along with the pressure regulator and fuel filter. The tank was drained as well and the fuel discarded. The car stood for a while then, when I came to drive it, no fuel pressure. There was a thump from behind when the key's turned (way louder than the relay clicking) which appeared to come from the fuel pump. The car went back to the garage who'd done the work; by the time they got around to looking at it, the thing worked perfectly.
I'm now about 1500 miles down the road in less than a week, and the fault's recurring. Once one evening, and it had cleared itself by the morning. And, again, last night. I've had the following happen:
- turn key, thump from the back, no fuel pressure, no start
- turn key, pump runs, start engine, runs for a few seconds and dies - the pump doesn't start back up when the engine's started
- turn key, pump runs, engine starts, all well.
Once started and running, the car's fine.
I was wondering if this was the result of dicky wiring to the pump - maybe there was a voltage drop somewhere which meant it had trouble getting going when the engine wasn't running. A quick test of this theory by seeing what happened when I tried to jump-start the car (which gave me 14+V at the battery terminals); still just got a thump from the back and no fuel in the rail.
I have an iCarsoft widget which I'll stick on the thing shortly and see if it sheds any light. In the meantime, any and all advice, suggestions and commiserations gratefully received.
Thanks --
Dave
