Fuel pump operation

[lukasdeopalenica]

Should the pump start when ignition is turned to on? Most of literature say no, because of closed flap inside the air flow meter. This should switch on together with starter motor and stays operating when engine runs. In my car, however, the pump starts immediately. I did some investigation in my car's electrics, and everything seems to be okay.

[archigraphe]

Basically,

The pump start in same time as the coil is charge....

You could hear it before you run the engine....as mainly car of this period...

[lanciamad]

Mine only works when the ignition is turned on, and the flap in the air flow meter moves, activating the pump.

[lukasdeopalenica]

Mine only works when the ignition is turned on, and the flap in the air flow meter moves, activating the pump.

It does mean when engine, or at least crank, revs, Isn't it?
My works at any time when ignition is on, and obviously is hearable. The flap switch is only for safety purposes. When I move the flap I can hear a click...

[lanciamad]

My understanding of it is, that the click you hear is when the flap moves in the air flow meter, it triggers a relay which then operates the fuel pump. As you crank the engine, air pulls the flap open operating the fuel pump and obviously the flap stays open during running.

[lukasdeopalenica]

in my case the pump's relay is energized (and the pump runs) when the ignition key is turned both to position On and Start and no matter if the flap is open or closed. Similarly to most cars, but in my eyes it does not match the literature data about Bosch L-jetronic systems.

[Thotos]

The fuel pump on the Bosch system should not be running when the ignition is on. The micro-switch switched on by the air flap should operate a relay to keep the pump running once the engine has started. To ease starting, there's a feed from the starter motor solenoid to the pump relay so the relay switches on the pump when the engine is being cranked.  So I'd guess that either the air flap micro-switch is faulty or badly adjusted, or the pump relay is faulty, or someone has played with the wiring and wired the relay straight to the ignition switch.   

[lukasdeopalenica]

 I tried to trace the circuits and found only that the dual-relay is okay and the micro-switch at the AFM is either. The problem I observe is that the dual relay's 86a terminal should be energized only with the starter motor, whereas the 86c is energized at the on and start positions. Both turn the fuel pump relay on. Is any circuit in the betas that is energized at the same time as the starter motor is?

[lukasdeopalenica]

I think I have found the problem at least partially. The 86a terminal was wrongly connected (via red/black wire) to a spare pin (fuel cut-off solenoid on carburetted models) that is energized with the ignition coil. It is located in the cable junction that also contains wiring of pressure/tempetature senders and the starter motor solenoid. However I can not find any spare socket dedicated for my red/black plug   Probably I need to connect it directly to the starter solenoid wire.

[lukasdeopalenica]

The red/black lead that I mentioned is circled in the attached picture. Can anyone owning IE version check and tell me where this plug should be inserted? I could not find any spare socket in the surrounding. I just connected it directly to the starter solenoid lead and now the pump operates as it should, however I am not sure if it is connected as it was designed originally.

[gengis]

On my 2000ie the two wires shown in your photo have their respective partners...
yellow male connection to yellow female connection.
red/blk male connection to red/blk female connection.

All four wires should be close by.

[lukasdeopalenica]

The yellow has its own partner (they run to the oil temp sender and the gauge and as the red/black were added in later versions - not included in the junction block) but the red/black one has just unfortunatelly disappeared, probably while the engine was removed.

[lukasdeopalenica]

While I was looking under a dashboard electrical bundles, just near a steering column, I have found 2 not used connectors. Comparing with a diagram shows that one of them (red/black wire) is an automatic gearbox provision while the other is marked as an "electric fuel pump control provision" (37A, light blue). The blue lead actually runs to the engine compartment but according to the schematic is connected to the oil pressure switch/lamp, however (sic!). While just in the same junction box there is the starter motor solenoid lead. I cannot see any sense for that arrangement. A mistake?

[Thotos]

No, not a mistake. The idea is that the pump will only run if the engine is being cranked by the starter motor or there is oil pressure i.e. the engine is running. It's a safety feature so in case of an accident the pump stops when the engine stops and the oil pressure sensor has zero oil pressure.

 

[lukasdeopalenica]

I thought the flap inside AFM is installed to decide whether the engine stops running and cut the fuel pump off.

[Thotos]

I thought the flap inside AFM is installed to decide whether the engine stops running and cut the fuel pump off.

Yes that's how it's done on fuel injected cars. The movement of the flap actually measures the amount of air drawn by the engine and a micro-switch when the flap is closed stops the pump. But carburettored cars with an electric fuel pump use the oil pressure switch method to stop the fuel pump when the engine is not running. Thing is, I didn't know that any Betas with a carburettor had electric pumps but perhaps Lancia wanted double protection? Or maybe made the provision for adding electric pumps to cars with carburettors.

[lukasdeopalenica]

Thing is, I didn't know that any Betas with a carburettor had electric pumps but perhaps Lancia wanted double protection? Or maybe made the provision for adding electric pumps to cars with carburettors.

Bingo! VXs have both the carburettor and the electric pump So this connector is provided rather for VXs not I.E.s
Thanks Thotos. But anyway I still have no idea where is my missing connector under the bonnet.

[lukasdeopalenica]

Digging up my picture resources I found some interesting ones. There is visible in there a relay circled in green. Analysing its location and connection it seems like the relay that switches both the starter coil and the fuel pump relay and is energized by the ignition switch. The question is: is it genuine or just an owners "upgrade"?
The other question is what a device is circled in blue? Something standard or aftermarket like an alarm unit etc.?  

[thecolonel]

Certainly thé relay in pic one is an owners upgrade. Thé black box in pic 2 looks
like an alarm/ immobiliser unit.