TheSamba.com :: View topic - 1977 fuel injected bay window fuel pump and timing issues

Wed Oct 06, 2010 11:11 am

I have recently removed my engine had the head rebuilt and installed the engine. I am guessing I have a wiring issue. Dual relay checks ok yet fuel pump is not running. I have jumped a wire to the pump and it functions with proper fuel pressure. The other issue is timing. Can the distributor be 180 off? Also what order do the wires go back on the coil? I'm new here please help my bus!! I want it!!

Wed Oct 06, 2010 11:32 am

Two cents to get you started. I believe your fuel pump relay will only kick on if the AFM is telling it to do so. You can test this by turning your key to ON and sticking a pencil down the AFM to manually open the flap. You should hear the relay click and the pump start running.

There are probably some precautions that should be inserted here, like "don't do that for too long" or whatever. I'm not sure. Maybe you can look this procedure up in a nice Bentley manual or do some forum searching for that.

At least this might help you isolate the problem...

Sun Oct 10, 2010 3:36 pm

When I trigger the AFM the fuel pump runs. I have gone through all of the fuel tests. Still not running. I believe I have the coil wires wrong. I have used the wiring diagrams yet it seems that they are all different. My coil is actualy getting hot. So more reason to believe I got it wrong. It fires runs for a second then acts like it runs out of fuel. The coil does feed a current to the ecu. Yet I'm stuck!!

Sun Oct 10, 2010 3:54 pm

You should have a white wire from the ECU going to the negative side of the coil. It should hook up right next to the green wire going to our condenser and points.

Sun Oct 10, 2010 4:25 pm

Ok guys thanks for the coil info. Now it will Start and run if I trick the airflow sensor. Otherwise it's not getting fuel. Any ideas on that one?

Sun Oct 10, 2010 4:26 pm

Ok guys thanks for the coil info. Now it will Start and run if I trick the airflow sensor. Otherwise it's not getting fuel. Any ideas on that one?

Sun Oct 10, 2010 4:34 pm

Black wire from the backup lites along the drivers side should be plugged into the + side of the coil. Check the inline fuse too as it also powers the dual relay.

Sun Oct 10, 2010 4:55 pm

Duel relay is getting power and fuse is good. Engine will run and idle if I stick a screw driver in the air flow sensor to open it a little.

Sun Oct 10, 2010 4:55 pm

Duel relay is getting power and fuse is good. Engine will run and idle if I stick a screw driver in the air flow sensor to open it a little.

Sun Oct 10, 2010 4:59 pm

Give your posts a few seconds to load or stop doubleclicking the post button :wink:

The fuse is just for the backup lights but the wire going to it also carries on and supplies the DR, if you are positive it's got power from the coil and the terminal/wire where it joins the DR isn't broken internally then suspect the DR itself.

Sun Oct 10, 2010 5:01 pm

Dual relay has been tested and is new.

Sun Oct 10, 2010 5:43 pm

Phishpimpin wrote: Duel relay is getting power and fuse is good. Engine will run and idle if I stick a screw driver in the air flow sensor to open it a little.

Pop the lid off the AFM and make sure the points for the fuel pump relay are closing as soon as the vane moves away from the fully closed position.

Sun Oct 10, 2010 6:24 pm

I am fairly confident it is a wiring issue at the coil. I have 2 black wires to the + side. To the - side I have red(to points and condenser) white going to cu, white/ green into harnes going through fire wall. This said harness going through the fire wall hosts a total of 3 wires. Black, black blue , and white/green. Can any of you identify where each of thees wires go.
The engine ran coming out only on three cylinders because of a burnt valve. I have checked all the other components. They all function within the recommendations of my manual.

Sun Oct 10, 2010 6:43 pm

Remove the green/white wire, it was for the test network, tape it up and avoid future issues. The black wire is power from the key and the black/blue is for the oil pressure sensor.

Sun Oct 10, 2010 8:26 pm

Now that the coil is wired correctly I'm getting some where. When the manual says the air flow meter should move freely, how free is that? Can the airflow meter be adjusted?

Sun Oct 10, 2010 9:02 pm

Leave the AFM adjustments alone or things will go from bad to disaster.

The engine should create enough draw to open the AFM door. If it only will start when the screw driver pushes the door, then the points inside the top may be out of adjustment. I also think that the the red and white wire from the starter is supposed to start the fuel pump when the key is turned to start.

Sun Oct 10, 2010 10:43 pm

SGKent wrote: The engine should create enough draw to open the AFM door..
Unless the vacuum leak elsewhere in the system is so big it can't create enough flow to open it.

Mon Oct 11, 2010 5:11 am

busdaddy wrote: SGKent wrote: The engine should create enough draw to open the AFM door..
Unless the vacuum leak elsewhere in the system is so big it can't create enough flow to open it.
yeah like the s-boot hose clamps are loose or something

Mon Oct 11, 2010 1:32 pm

So I went ahead and totally jacked around the afm. Bus is now running and going down the road. Oops should have checked here first. Hopefuly I haven't created a huge problem. Thanks to all of you for the help. I would not have gotten this far without it!!

Mon Oct 11, 2010 1:35 pm

Phishpimpin wrote: So I went ahead and totally jacked around the afm. Bus is now running and going down the road. Oops should have checked here first. Hopefuly I haven't created a huge problem. Thanks to all of you for the help. I would not have gotten this far without it!!
:shock: :? :roll: Can't wait to see how this ends.