I second this. Get a voltage reading at the fuel pump. It's quick to do, and will stop you chasing your tail through the oh so consistent (!) wiring set up. Having replaced two fuel pumps in the past two months (an FI and a Carb.... And actually two on the carb), they can be idiosyncratic things.81SPIDERMATT wrote:a failing fuel pump will imitate your symptoms also ... to be sure you would need to test the voltage at the pump ... if you are getting good volts at the pump than most likely the relay is doing its job ... if no voltage then I would suspect the relay
If voltage is good - remove the pump. Depending on whether it's stock or after market you may be able to take it apart and see whether it's got crud in it or not.
If no crud, check the filter that's straight after the pump on the way to the engine. It could be that that a crud buildup is causing the pump to overwork and fail (sometimes) when warm.
If crud in pump, check to see where it's coming from. Pull the fuel sender in the top of the tank (carefully .... It's very easy to shear those ridiculous 7mm nuts and studs). Is the tank clean? If your sender has a little brittle bag at the end of it - is it decaying? Is it missing (and sloshing around in the tank decaying?) - regardless of which of the various plumbings is being used for the actual fuel intake).
Lastly - what condition are the hoses? Are they original? Aftermarket? The various additives to modern gasoline degrade older hoses... You may be looking at replacing them.
I would be looking at these four places as potential problems, filter, pump, tank, hoses.
I'd suggest that at a minimum you'll want to replace the fuel pump and filter, and potentially clean out the tank if you find a source of crud. You may get lucky and it's just the time-driven gasoline crud build up in the filter that has finally caused a problem. Don't underestimate what a bad hose can do - and they're not hard to replace.
Good luck! And take care when messing about with fuel..... And be gentle with those 7mm studs!
Andy
