Its a Mk 1 with ABF I finally turned over the car last weekend, but it wouldnt run [:^(] I noticed the fuel pump kicked in and then stopped. I thought it was odd as on injected cars it runs until it reaches pressure. The pump is off an injected car (I cant remember what it is off) and is an in tank VW lift pump that fits the Mk 1 tank. The flow and return are connested properly as is the wiring. Today I disconnected the supply line to the fuel rail and turned on the ignition to see if it was pumping fuel. The pump works but only for a couple of seconds and then stops. Turn the ignition off and on and it does the same thing. What would cause this? Thanks for any advice Regards Paul
The pump should prime for a few seconds when you turn on the ignition. Then the ecu should turn it on whilst cranking and running. Are you using standard management?
Thanks for the reply. Yes, original ECU I assume the ECU provides the switching power to the relay and the relay has an ignition live? Is it ok to stick a multimeter onto the ECU pin to see if it has voltage? If it doesnt then could it be an immobiliser issue? I was sold it, the two looms and the engine complete by a genuinely nice VW enthusiast who swore it wasnt immobilised. What other symptoms of an immobilised ECU should I look for? If it is can it be re-programmed?
What is the ecu number? that should tell you if it immobilised. But it should start for a few seconds. The fuel pump relay is turned on by the ECU switching the wire 6 on the ECU plug T68. It should be a yellow/Blue wire connected to G1/3 on the fusebox. If you need a diagram i can email you it if you pm your address. to aid testing
Found a link to an ABF diagram. One of Rubjonny's i think http://vwtech.no-ip.info/downloads/g3abfecu.pdf
Thanks chaps I appreciate your help Two more..................... I`ll check out the ignition as its on coil and TCI unit - coil amp done away with (unreliable I`m told) It sounds like it might be immobilised? Where can I find out which ECU`s are immobilised? I see tshirt2k you`re in Herts - so am I :-)
The immobilised ecus have a part number ending AE BE or CE. The mk3 coils are sh*t tci's are better. Yes I'm in herts, just off the A10.
Hi all, I`ve had another look. There is a good regular spark from the main HT lead to the dizzy once its turning over so I reckon its registering the engine cranking and firing ok. The ECU has an AB designation so assume it isnt immobilised. So its got to be a fuel pump issue in my view. It runs with a funny groaning noise (no carpet or cover fitted) sounds like a low "rrrrrrrrrrrrrrrrrrrrrrrrrr" for about a second and a half and pumps out fuel at full bore immediately so I dont think its the pump - or is it? Having said that I would have thought the pump ran quietly so is the groaning noise the norm or is it just that its exposed? I`ll trace the wire and assume its a permanent feed while the ECU is energised and the engine is running. I assume its a relay switch wire for the permanent live to the relay? Can I bypass the relay temporarily to see if she runs? I might run an ignition feed to the pump. So near and yet so close [:^(][:^(][:^(]
You may want to check/change ecu and fuel pump relays. You can earth the fuel pump relay at the fusebox G1/3. look in fusebox faq. The relay is internally powered in the fusbox. Only coil earth is what switches it on. fuel pump is noisy BTW
I have the Mk1 Golf CE1 fuse box so G1/3 doesnt exist :-( ECU and pump relays are brand new VW Bridged the relay terminals, pump runs continuously but it wont start. ISV clicks, ECU has power, good spark at dizzy. I cant find the yellow blue wire coming from the ECU into the cab. The loom was cut and shut to suit a Mk1 by another very helpful chap on this forum but I`ve not heard from him yet. Again, its a Mk1 Golf with the CE1 fuse box so G1/3 doesnt exist :-( You have PM, thanks.
Looks like you need to trace this. Although it must work due to it being pulsed on ignition. Are you sue the ECU/FPR etc is powered from Track 15 whilst cranking? Haven't got CE1 fusebox diagram so dont know what wires are what.
if you're using the original fuel pump relay and wiring, the problem is you dont have a rev counter signal which is compatible with your fuel pump relay. it needs a rev counter signal from a mk1/2 coil, if you're using a mk3 coil the signal wont trigger the k-jet relay. was this one of my looms? if so i would have wired it to use a mk2 coil and tci unit, unless you specifically told me not too... plus id have wired it to use a 67, 80 or 167 fuel pump relay, not the older k-jet style one(although it will work with k-jet relay if its using a mk2 tci setup). also if it was one of my looms, did you fit an ecu relay 30 to the spare relay holder above the fusebox?
Hi John Yes it is your loom. Its a mk 2 coil and wired into the TCI - that side of it works fine (I get a strong spark when its turning over) It has a brand new VW 167 pump relay in fuse board relay position 2 and it has brand new 30 ECU relay in the block you wired. It uses a 53 relay in the other block you wired. I am sure its a simple thing but isnt a blue and yellow wire supposed to feed the relay continuously according to wiring diagrams but I cant see it so dont know if thats an issue. I stiill dont know what is making the pump kick in and then stop. If it starts up then what is stopping it? Equally I ran the pump by bridging the terminals and it didnt cough once when turned over. If the pump is u/s I`d go down that route but I need to get the pump running continuously first. Any help will be appreciated.
the blue/yellow wire is the fuel pump relay earth trigger from the ecu, its the ecu which is making the pump prime then stop, sounds to me like the ecu and relay are working exactly as they should I'm thinking problem isnt the pump, relay or the wiring at all (if it was, bridging the relay would make the car run fine), rather its something else. my first thought would be the crank sensor, without that the ecu wont see an engine signal and then will not trigger the pump when the engine is turning over on the starter motor. did you remember to plug in the thin red wire with the massive yellow plug on it to plug N on the back of the fusebox? thats the power feed for the fuel injectors
Good news - I hope so as something is switching the pump and it has to be intelligent. The pump runs then stops when the ignition is turned on (before turning it over) To get it to run again the key has to go right back past the accessory stage and then back to ignition on so its ignition triggered on but must be triggered off by the ECU I would imagine as the relay isnt that clever? Yes but its worth putting a multimeter across it. How do I test the crank sensor. Its undisturbed so in theory should be ok? I have another s/h one so could swap it I suppose. there are two and I assume its the one at the lower r/h front of the block and the other is a knock sensor? Thanks for the help (so far) it really is appreciated.
i might be wrong but i think you can check the crank sensor operation via vag-com, you may be able to test with a multimeter but i have a feeling you need something that can check a pulsed signal, this is out of my experience. with the crank sensors i just advise to buy new, as if original they wont have a lot of life left in em. gsf sell them for around 50 on the fuel rail if you check the red wire you should get 12v whenever the pump is on, so in your case bridge the relay again it would be easier. test from the red wire to the battery -ve, the other wires are earthed via ecu when it want the injectors to fire, so obv engine would need to be cranking and again you would need summat capable of seeing a pulsed signal. might be worth looking at the round plug, they can be a real bugger to fully lock into position can take a hefty twist to get both halves to lock in place. also check the -ve on the ecu temp and outside temp wires for continuity to ground, there is an earth on side of head at the back which can get dirty with age.
Hi John I`m ok with the rest but can you elaborate on the above please? Do you mean temporary wires or temperature wires. 1) ECU temp? If thats the earth then they are all connected to the earth `ring` behind and above the fuse box The ECU and its cradle are not directly earthed, should they be? I thought the earth was in the loom? 2) Outside temp? 3) Side of what head? If its the cylinder head theres no earth wire? An additional aspect is that I havent bothered filling it with coolant yet but cant see this being an issue? Or am I wrong (and stupid)? Another aspect is that there are spare wires coming off the TB potentiometer loom branch that I believe are for the crankcase emission system but these are cut and terminated seperately so the circuits are broken. There is another set of wires that run along the front of the engine that diverts away from the engine plug loom just before the plug that I believe was for the a/c and that again I have simply left unconnected and taped up. Regards
