Over fuelling on starting

[wizwilson]

Hi Adrian, thanks for the links, got them ordered, also found second hand unit on ebay for £50 so am hopping it will work

[Theclash]

You have defiantly blown the ecu.......it's the same thing on golf mk2 running digi
On the golf there is a earth that goes to gearbox which is usually overlooked when the gearbox as been off clutch etc, if not replaced it blows something in the ecu which causes the injectors to run constantly ,if when you first turn ignition key you don't hear the fuel pump prime then stop but run continuesly then there's your problem
I don't know where the earth is for your ecu but on the golf it fastens onto the gearbox
You need to find that Earth and make sure it's clean with a good connection before you try it with your replacement ecu else it will blow that aswell

[wizwilson]

Hi, thanks for that bit of info, it obviously hasn't happened on T25 that much if at all, think the fault happened after i had replaced all the earth eyelets with new solder ones, but i had left one of the bolts loose, so think when i tried to start it, i spiked it ....

[Theclash]

It's a very common problem on the digi mk2s
The earth has to be a very good connection
ecu's are cheap as chips for the golfs unfortunately I would imagine like everything for the t25 it will be expensive

[wizwilson]

Have found another company in Plymouth that will test and repair these ECU for good price and quick turn round, they are called " The ECU Doctor " there phone number is 01752346437, web address http://www.the-ecu-doctor.co.uk" onclick="window.open(this.href);return false; give them a look.

[wizwilson]

Just to let you all know the second hand ECU i got off of ebay arrived today, fitted it and she fired up straight away, am so happy but lessons learnt DO NOT LEAVE ANY ENGINE BAY EARTHS LOOSE, as I'm sure thats what spiked the old one.
Will probably get my old unit repaired so have a spare, am just finishing the fitting of oil pressure gauge at front of vehicle, and tidying up of wiring round dash and fuse box, will post pictures when finished.

[mark]

pleased that you've got to the bottom of the problem .................... and returned to confirm the fault

mark

[spanishfly]

Hi, I too have a massive over fuelling problem but may not be ECU. If I remove the fuel return block it and measure 30seconds output from the pump I get 900cm3 rather than the 500cm3 Bentley suggests! Could this be the regulator? I don't have a pressure gauge. Cheers

[wizwilson]

Hi, will the engine run with the system connected all correctly, if so then unlikely to be same ECU fault.

points to check when you key on does the fuel pump run for about 5 seconds then shut off, if so that's correct.

if you pop out 2 of the injectors and switch the pump on do you get fuel gushing out out, if just the odd drip that's ok, but check other 2 just in case one injector has gone down.

make sure you have good vacuum at pressure relief valve, and when you disconnect vacuum pipe to pressure relief valve it should make a difference to the running.