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fueling problems

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Hello,
I have acquired a 1981 924 as a non runner and am trying to get it back up and going again. It had a water leak that put water into the fuse panel. I have fixed the leak, cleaned everything up and the electrics is back working like a dream again. My problem is now it isn't getting fuel. I removed the fuel line at the fuel distributer and had a mate crank over the engine and I am just not getting fuel. I checked the relay and it appears good, i replaced the relay and am now thinking i have an issue with the fuel pump. My main question is does it have a pump in the petrol tank and a main fuel pump like others with this type of fuel injection of does it simply have a main pump. I have been through the haynes manual (which is rubbish. lol.) and can't seem to find a reference to a lift pump in the tank so i am leaning towards it not having one. Where abouts is the main fuel pump located? Thanks in advance and sorry for the long post. Trying to get her up and going so i can get it through MOT and figure out what other work i need to do. lol.
 
Try the DME Relay (About £20) before getting too far down the line with the Fuel pumps.
Might save a lot of grief...

SteveS
 
First of all make a jump lead like it shows in the Haynes (p85-87) to illiminate the relay itself. (make up a lead with MALE spades from 20 amp cable to short out the sockets for pins 30 and 87). Put a voltmeter across the terminals of the pump. The view on page 89 clearly shows the pump when viewed from below the car looking up and to the right. Get a friend to make the connection whilst you check the voltage. I have a '79 with two pumps but others have '79 models with a sinlge pump.
Terminal no. 1 on the relay connects to the coil, and I dont think the pump will run unless the relay detects voltage rise and fall here, as a safety measure, e.g. in an accident with severerd fuel lines, and the ignition on what would stop the pump from running? Could be a red herring, but worth a check. I have had the misfortune of having the pump fail, and this is usually accompanied by a melted relay socket, but yours could just have siezed due to inactivity.

 
(From Bgodkin) Sorry my log in stopped working when i changed my email. lol. computers eh.

Is DME a brand of relay or a different type? Where would I be able to find it from? I had bought a new one from euro car parts but i know how their electrical bits can be.

I'll try jumping from pin 30 to 87 and see where that gets me. I also check between pins 1 and the coil to see if i have voltage while cranking. I just moved house and my new garage is full of building supplies at the moment. Hopefully by the end of the week i can get in there to climb under it.

Thanks for the help and I will keep you all posted.

Brad

 
The DME relay applies to 2.5 litre 944 engines with Bosch motronic engine management. This is a regular occurrence with the 944 engine electronics. The 2 litre lux does not have motronic but rather misleadingly Kjetronic, as there are no real electronics on the injection system. The action is continuous, and the fuel pools behind the inlet valve when it is shut, and atomises again when the inlet valve opens by the spray acting in the pool whilst under suction ffom the cylinder.
 

ORIGINAL: 924nutter

The DME relay applies to 2.5 litre 944 engines with Bosch motronic engine management. This is a regular occurrence with the 944 engine electronics. The 2 litre lux does not have motronic but rather misleadingly Kjetronic, as there are no real electronics on the injection system. The action is continuous, and the fuel pools behind the inlet valve when it is shut, and atomises again when the inlet valve opens by the spray acting in the pool whilst under suction ffom the cylinder.
Click to expand...

Ahh. The DME Brain. That had me a bit confused. I thought maybe there was a certain brand of relay. I'm pretty familier with K-jet inection. Same as my Golf and alot of other VAG cars I've had. Pretty simple until something goes wrong and then a pain in the neck to sort sometimes. lol. Hopefully get some time to mess with it today. I'd like to get it going again. Hate seeing it sitting.
 
Except the Golf GTI fuel pump relay has round pins, and never suffered from the dreaded warm start. The fuel injection couldnt be easier to understand. Stick your arm out of your car window and you have the basic principle. Now, the faster you go the more your arm deflects. Connect your arm to a linkage that regulates fuel flow, more deflection more fuel.
Now cut a disc and put it in a tube, and let the engine suck past it. connect this arm to a method of regulating fuel flow and that's it.
ON the jetronic this regulator is a spindle with about an 8mm wide groove in it that slides up and down in a housing with four slots, one per cylinder.
the spindle works like the slide in an old Amal side draught carburettor. gradually opening more of the slot to fuel flow. ( yes i have had a metering unit to peices. ) The pivot is a parallelogram with one side adjustable for length. Brilliantly simple concept. 3 moving parts.

 
i take it the 924 suffers from warm starts then? lol. I wonder... I have a fuse panel from a 1989 golf GTI. They hook into the car the same way. I woner if i could do a bit of wire tracing and schematic chasing and use that one. That would get rid of the old style fuses anyway.

No warm start problem on my golf. Thanks to it being cammed and a drilled and gutted airbox with a k&n it doesn't care for running on cold mornings though. lol.

Thanks for the help
 
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