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99a4wagon
12-29-2010, 03:40 AM
OK swapped the motor in my a4 and now it wont start. Its cranks fine but no starting. The plugs are dry so I think its no fuel. Also I traded my chipped aeb ecu for a non chipped aeb ecu. Maybe their different not sure.

Any input.

99a4wagon
12-29-2010, 10:40 AM
Cmon guys anyone?

zrowcool
12-29-2010, 10:51 AM
need way more info. cold be a bunch of stuff from the vague post you made. start with the fuel pump and go from there. connect the pump drectly to a 12v source and see if it pumps. if it works then you need to look at the fuel pump relay and fuses. if it doesnt then you need a new pump. if its not the pump or relays then check to see if the lines are correct and if they arent pinched in any way. than i would look at the spark to make sure the ignition system is functioning.

process of elimination is the only way to get it sorted out.

biketsai
12-29-2010, 10:51 AM
Alright, so no fuel. Have all fuel lines hooked up right? Fuel pump fuse still good? etc etc

99a4wagon
12-29-2010, 07:10 PM
Alright, so no fuel. Have all fuel lines hooked up right? Fuel pump fuse still good? etc etc

Stupid question where are the fuses and relays for the pump. Theirs a funny sound with the key turned in the on position. Almost like a faulty relay. When I pulled the motor I just pulled the fuel rail aside.

biketsai
12-29-2010, 07:15 PM
They are located with every other fuse in your car, on the side of the dash drivers side. I think its spot 25 or 23? Its in your manual, might as well just check them both

99a4wagon
12-29-2010, 07:18 PM
They are located with every other fuse in your car, on the side of the dash drivers side. I think its spot 25 or 23? Its in your manual, might as well just check them both

Ic. Wasn;t sure if they where elsewhere. My next question would of been what number. Thanks Ill check those out first.

walky_talky20
12-29-2010, 07:29 PM
Does the fuel pump run when you turn the key to the ON position (don't start the car, just put key in and turn it so the dash lights come on). You should be able to hear the fuel pump prime for about 2-3 seconds. It should do this every time you turn the key on. It should also run during cranking (obviously more difficult to hear due to noise from the engine). If the fuel pump is running, then check for spark. If spark is good, you just have a fuel issue. If you are missing fuel AND spark, you've got one bigger problem like a crank sensor or ECU issue. Alternatively you could have 2 separate issues (1 issue with fuel and a separate issue with spark), but that is unlikely.

99a4wagon
12-29-2010, 07:37 PM
I dont think I hear fuel pump. I hear a distinct whine which I dont think its the pump because the whine is in engine bay and it stays on. Also I hear some clicking from around the abs module.

zrowcool
12-30-2010, 05:17 AM
whine is probably the throttle body and the clicking probably the tank vent solenoid. chek the pump with 12v. you can access it under the rear seat cushion.

99a4wagon
12-30-2010, 11:21 AM
whine is probably the throttle body and the clicking probably the tank vent solenoid.
Is this normal?

99a4wagon
12-30-2010, 04:13 PM
Ok the fuel pump if def not priming. I pulled and check every fuse. There are 4 wires that run into the fuel pump. What ones should I jump?

http://img413.imageshack.us/g/sany00052.jpg/

My buddy said it might have to be reset via vagcom from sitting so long without battery. Can anyone confirm this? What about the fuel cutoff when you get into an accident?

walky_talky20
12-30-2010, 09:22 PM
- Are you getting spark? How about injector pulse? These are the first things to check.
- What about this ECU? Is it a different one since the car last ran? In other words, is this ECU an unknown variable here (new to you)?
- Do you get a Check Engine Light when you turn the key to the ON position? (This is important)

- Fuel pump is fuse #28, 15amp.
- At the fuel pump, the supply wire is the green/yellow wire (pin 1). Ground is brown (pin 4).
- I would not chase the fuel problem any further until you know if you have spark or not.

VR6Bomber
12-31-2010, 08:50 AM
codes make it alot easier

99a4wagon
12-31-2010, 06:29 PM
- Are you getting spark? How about injector pulse? These are the first things to check.
- What about this ECU? Is it a different one since the car last ran? In other words, is this ECU an unknown variable here (new to you)?
- Do you get a Check Engine Light when you turn the key to the ON position? (This is important)

- Fuel pump is fuse #28, 15amp.
- At the fuel pump, the supply wire is the green/yellow wire (pin 1). Ground is brown (pin 4).
- I would not chase the fuel problem any further until you know if you have spark or not.

Spark is unknown I didn't check because no fuel is getting to the plugs(dry and don't smell like gas).
The ecu came from a running aeb motor. The kid drove the car to my house and drove off with mine.
Check engine light stays on with key turned over(I believe that means the ecu is on)
I checked every fuse
I will check those wires if I can clean the dirt off to identify them.

walky_talky20
12-31-2010, 07:09 PM
I'd check the spark real quick just to make sure you're not dealing with a larger problem (crank sensor, bad ecu, etc). Takes 2 seconds. Then I'd check for power at the injectors or power at the fuel pump, to see if the fuel pump relay is working. If no, I'd go to the relay location and check things out there.

99a4wagon
01-01-2011, 02:54 PM
I'd check the spark real quick just to make sure you're not dealing with a larger problem (crank sensor, bad ecu, etc). Takes 2 seconds. Then I'd check for power at the injectors or power at the fuel pump, to see if the fuel pump relay is working. If no, I'd go to the relay location and check things out there.

Relay is behind kick panel on drivers side right? Do I have to keep turning the key on and off to check for power at the pump?

walky_talky20
01-01-2011, 05:10 PM
It should have power for a few seconds when the key is turned on (for priming). Also it will have power whenever cranking as well.

Do you hear/feel the fuel pump relay clicking?

SeekB00st
01-01-2011, 05:29 PM
check spark, check icm, make sure ECU is compatible. Check to see that the fuel lines are connected properly and not in reverse - on the fuel line.

SeekB00st
01-01-2011, 05:30 PM
Also make sure that there the vacuum line for the fuel pressure regulator is hooked up properly.

99a4wagon
01-01-2011, 06:38 PM
OK i test the spark and I held the sparkplug in with zip ties and I dont think Im getting spark.

99a4wagon
01-03-2011, 11:13 AM
Bump for needing info.

going_crazy
01-25-2012, 07:55 PM
was the issues resolved; i am running into the same issue with my audi; I appreciate the help.