fordsteve77

Hi all have had this problem since buying a restoration XR3i Cabby:
the previous owner had an ignition live going to the fuel pump RED/BLACK pin where the fuel pump relay should be.... which ran fine but I didn't like it so I pulled all of his dodgy wiring out...
I purchased a NEW Lucas relay (replaces the purple one) and now it primes the pump for about 2-3 seconds I start the car and after that 2-3 seconds of primed fuel it stalls...?
Mine is also the MFi engine and the fuel pump relay runs in conjunction with a speed sensing module Bosch black 6 pin ( 2 rows of 3) part no 0280230113 or 0280230116
Also the RPM rev counter does not work I believe its linked to the fuel relay & speed sensing module

martysmartie

iTrader: (1)

It sounds like you have not wired it correctly.

Maybe the speed sensing module is not grounding, hence not closing the relay, is that defiantly the correct pin? (I don't know the Bosch management that well)

Re the rev counter, the ground connects to the coil, if you have a look you should see two green wires?

Martin

fordsteve77

Well 1 green and 1 green/red

Here is a pic of the 2 relays I have tried 1 original and 1 brand new they both prime the pump for 2-3 seconds

and here is a replacement speed sensing module its has 113 last 3 digits of bosch number mine had 116 last 3 digits

Speed sensing module pin outlays

31 = earth (shared with fuel relay below)
15 = switched live
88a = over run shut off valve
31b = thermal time switch
31e = cold start valve
1 = coil negative from coil supressor

Fuel pump relay pin

1 = coil/rpm instrument panel
15 = switched live
87 = fuel pump
30 = permanent live
31 = earth (shared with speed sensing relay)

The safety module is located under the facia panel on the driver’s side and is coloured purple (see illustration).
Its purpose is to shut off the power supply to the fuel pump should the engine stall or the vehicle be involved in an accident. The module senses ignition pulses, and cuts the fuel supply if the ignition pulses stop.
The fuel shut-off valve system is an economy device whereby air is drawn from within the air cleaner unit through the shut-off
valve and directed into the ducting chamber above the air sensor plate causing a depression. This then causes the sensor plate to drop which, in turn, shuts off the fuel supply.

The valve is operated by signals from a coolant temperature sensor and a throttle position sensor. The shut-off valve will only operate under the following circumstances:
a) When the engine coolant temperature is
at or above 35°C (95°F)
b) When the throttle is closed and with the
engine speed decelerating from speeds
above 1600 rpm

The engine speed is sensed by a speed
sensing module which is coloured black and
located beneath the facia panel on the driver’s
side

fordsteve77

Any help most appreciated

fordsteve77

Checked earth for both relays/modules
checked all cables were in right places
still not starting properly cranks over fires and then dies
what is the suppressor for off the coil ?
Pictured:
there is 12 volts coming out of the green/red wire going to this suppressor but after suppressor the green/red wire there is 0.29 volts

fordsteve77

Also now it doesn't want to start on the bridged wire constant live to fuel pump, which it did before...?
Cranks over sort of fires then dies, very frustrating....

mk2grp1

could the decel cut off be at fault, i`m guessing it could be disconnected whilst on your driveway, its simply a means of killing the engine and shutting down fuel pump in the event of an accident, that was my understanding of it, thats what the speed sensing relay was for, i think , , also i have 1 here from a 1983 xr3i it ends in 113, part number 83AB 12B 528-AB

fordsteve77

Yeah I bought a replacement speed sensor relay/module ends in 113 as in pic below:
My original one ended in 116 had the same 6 numbered pins though

FinnKay1982

Did you ever get to the bottom of it?