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blazerbrad · 03-14-2007, 10:05 AM

Have you hooked up a diagnostic tool yet? Do you have the capability to do this (i.e. is the diagnostic port installed)?

Please don't take this personally, but you are wasting a lot of time and money throwing random parts at the engine and hoping you get lucky.

Anyway, here are a few places to start. This is assuming the ASD relay is good.

**NOTE: take a good look at any connectors you unhook for bent pins, loose wires/broken wires, dirt, or green crud (corrosion), my guess is this will the be the ultimate cause of the problem.

1. actuate ASD (we usually do it with the DRB tool but I believe turning the key on will do it also, but remember that I believe it will only give power to the fuel pump for a few seconds upon initial key-on)
2. touch fuel pump relay (located in the power distribution center...big fuse box), it should pulsate when you first turn the key on
2a. yes - turn ignition off, disconnect FP relay, (diagnostic procedure does not say to turn ignition back on???), probe cavity D on the PDC (location where the relay was), is voltage above 10 V?
2b. no - disconnect FP relay, turn ignition on, probe cavity A on the PDC (location where the relay was), is voltage above 10 V?

Also, while the FP relay is out check the resistance between pins 85 and 86. The resistance should be below 100 ohms. If not, the relay is probably bad.

This is further down the chart, but it would probably we worth it to do a visual inspection of the fuel pump harness connector (it's a 5 pin flat style connector, but can't remember exactly where it is).

If you get a chance do these procedures and see what the results are, then we can go from there.

03-14-2007, 10:05 AM	#47
blazerbrad - CORE Member - Join Date: Feb 2007 Posts: 831	Have you hooked up a diagnostic tool yet? Do you have the capability to do this (i.e. is the diagnostic port installed)? Please don't take this personally, but you are wasting a lot of time and money throwing random parts at the engine and hoping you get lucky. Anyway, here are a few places to start. This is assuming the ASD relay is good. **NOTE: take a good look at any connectors you unhook for bent pins, loose wires/broken wires, dirt, or green crud (corrosion), my guess is this will the be the ultimate cause of the problem. 1. actuate ASD (we usually do it with the DRB tool but I believe turning the key on will do it also, but remember that I believe it will only give power to the fuel pump for a few seconds upon initial key-on) 2. touch fuel pump relay (located in the power distribution center...big fuse box), it should pulsate when you first turn the key on 2a. yes - turn ignition off, disconnect FP relay, (diagnostic procedure does not say to turn ignition back on???), probe cavity D on the PDC (location where the relay was), is voltage above 10 V? 2b. no - disconnect FP relay, turn ignition on, probe cavity A on the PDC (location where the relay was), is voltage above 10 V? Also, while the FP relay is out check the resistance between pins 85 and 86. The resistance should be below 100 ohms. If not, the relay is probably bad. This is further down the chart, but it would probably we worth it to do a visual inspection of the fuel pump harness connector (it's a 5 pin flat style connector, but can't remember exactly where it is). If you get a chance do these procedures and see what the results are, then we can go from there.