GTI build has started

So We are trying to wire it all up without the 109 relay. Right now we have power to ECU it scans everything fine except for what isn't hooked up. Still can't get the car to fire though. At first when we flipped the switch, you could hear the solenoid click, and a whirring inside the pump for a second. Then we changed something (can't remember what) and the whirring stopped when you turned on ignition, and only the solenoid clicks now. We are still getting fuel to the injectors, but it's not really spurting out like I'd think it would. Not getting any unburnt fuel out of the exhaust either.

So, I'm thinking the qi or qa or whatever it's called in the pump isn't opening/turning on and allowing full fuel to the injectors, though its enough to get fuel out of the pumps return line. I'm trying to find a pinout for the pump harness now, so we can run the proper wires to the ecu instead of the 109, and run the power wires off a switch.
 
Can't get the quantity adjuster arm to sweep after ignition is turned on. Got it to work once, don't know how, but it won't do it again.

Ohm'd out the 5/6 pins in the pump harness, measured 2.8, so we cleaned it up and got it down to .8 which is what I've read it should be. Still no luck getting the qa arm to sweep.

Then measured voltage's out of the ecu side of the harness. Except for the grounds, they all had 13, 5, or 2.5 volts all the time, with or without the ignition on. Even unhooked the ignition to make sure it wasn't shorting and doing something freaky.

Unhooked the ecu's plenum plug and now all the pins read zero.

Can anyone check their harness and let me know which pins have voltage with ignition on and off?
 
None of the plenum plugs have power from the ecu.

You should really get a bentley manual for the MK4 and plot out all the plenum plugs from each car and correctly wire it up and be done with it.
 
Here, let me do you a flavor
http://www.autozone.com/repairguides/Volkswagen-Cars-2000-05/Fuel-Systems-2002/1-9L-Engine-Turbo-Diesel-Fuel-Injection-Dfi-66kw-Code-ALH-With-Automatic-Transmission-From-September-2001/_/P-0900c152801beece

http://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c152801be2dd

not sure which ones you have exactly, get the old engine code and google "autozone repair guide ALH" or replace ALH with the other one, it should take you directly where you want to go.
 
JFettig said:
None of the plenum plugs have power from the ecu.

You should really get a bentley manual for the MK4 and plot out all the plenum plugs from each car and correctly wire it up and be done with it.
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We re-wired them using the bentley manual, but I don't think it worked out lol. There are the random voltages at the pump constantly until we unplug that one plenum plug, which I know can't be right.

JFettig said:
Here, let me do you a flavor
http://www.autozone.com/repairguides/Volkswagen-Cars-2000-05/Fuel-Systems-2002/1-9L-Engine-Turbo-Diesel-Fuel-Injection-Dfi-66kw-Code-ALH-With-Automatic-Transmission-From-September-2001/_/P-0900c152801beece

http://www.autozone.com/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c152801be2dd

not sure which ones you have exactly, get the old engine code and google "autozone repair guide ALH" or replace ALH with the other one, it should take you directly where you want to go.
Click to expand...

Thats awesome, had no idea autozone had that.
 
Does the immobilizer cut fuel or not allow cranking? Will it throw a code if the immobilizer is active?

With an immo delete, do you still need the sensor in the ignition?
 
you can fire the engine up with an immobilizer active and the wrong key(not adapted), but it'll shut down after a few seconds.

VCDS - engine - adaptation block 91 should show 1 if IMMO is off, 4 if IMMO is on.
 
Ok, so either way, it won't prevent the qa from doing it's sweep with ignition on. Damn this is killing me.
 
Are you communicating with the ecu yet? I recall you saying somewhere that you couldn't with vcds?
 
JFettig said:
Are you communicating with the ecu yet? I recall you saying somewhere that you couldn't with vcds?
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Yeah got that fixed. Everything works now except the power windows, sun roof, and the qa. The qa harness has constant 2.5, 5 or 12 volts to all the powered pins, thats why I'm convinced that a wire somehow got crossed somewhere.

I think I found a complete harness out of a 2000 jetta 5spd, everything from the radiator to the pedals. Gonna attempt to swap that in, and then trouble shoot from there.
 
You can wire the thing to run with a toggle switch.... you really don't need all that stuff.
 
JFettig said:
You can wire the thing to run with a toggle switch.... you really don't need all that stuff.
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Not with out proper diagrams lol. And the qa is variable. if it was just on a switch, it would be full fuel or no fuel, right?
 
you have proper diagrams. You just have to learn how to read them. They are really weird but it makes sense once you figure it out. There is a page in the bentley to show you that.

No you do not put a switch on the QA!!! You just put a switch on the power on pin on the ecu, it triggers the 109(wire it into the harness!) the whole thing is powered up by putting 12v to T121/37, its so simple. Don't even touch that half of the engine harness.
 
I haven't even begun to understand these diagrams, i have friends that do it for a living though, so I asked them to rewire that 6th plug. Everything works except for the qa. The weird part is there is a constant 12 volts to some of the pump harness pins, and a constant 2.5-5 volts on some others. Always, whether ecu is on or off, and they voltages never change. We can't figure out why. Maybe this ecu is toast?

Why do you need the 109 if you repin the plenum plugs?
 
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Try checking those pins that have 2.5 and 5 volts after about half an hour after trying to crank it. Dang germans and ecms that goes to sleep later. I dont know for sure if vw does it, but the benz i used to work on would stay live for atleast ten minutes after you locked the doors. And just because voltage is available with a voltmeter doesnt mean it is doing anything.
 
crackerman said:
Try checking those pins that have 2.5 and 5 volts after about half an hour after trying to crank it. Dang germans and ecms that goes to sleep later. I dont know for sure if vw does it, but the benz i used to work on would stay live for atleast ten minutes after you locked the doors. And just because voltage is available with a voltmeter doesnt mean it is doing anything.
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It isn't doing anything lol. And the power there, and unchanging, constantly. Drains the battery in a matter of hours.

JFettig said:
The 109 relay is the relay that supplies the power to the ecu.
Click to expand...

It's all re-pinned and comes on with iginition toggle.
 
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