1998 626ES 2.5L lack of fuel after engine swap SOLUTION
I have a swapped the engine after seizing the engine, the cam sensor failed. Never the less, the car sat for 3 years and I just swapped the engine in June 2012. While the car was stored, at a friend's shop, someone hacked the main fuse box and who knows what else. I fixed the fuses, but I am not sure about the relays in the main fuse box. The new engine turns over and I have spark. The ODBII does not indicate anything wrong (other than recent power failure due to battery being disconnected) and the PCM is getting power. The engine will run with manually adding fuel. However, I am not getting any fuel from the tank though normal means.
http://www.justanswer.com/mazda/6a3am-mazda-626-inertia-switch-1999-mazda-626.html
I found what appears to be the fuel relay location according to this post at just answer. When I test the yellow wire with the relay plugged in, I do not get power. However, I get power when I jump the wire at the relay location. My pump does not get power when I supply power directly to the yellow and black (ground) according to the wiring schematic.
In these pictures I show the plug at the rear of the fuel tank and the yellow wire from the relay. In the fuse box, the white relay is the location of the yellow wire and is labled "Circuit Relay." I am stumped. My thought is that I have two issues happening at the same time. The first is that whoever damaged my fuse box by trying to "pry" out the fuses, swapped something or damaged something in an area I am not familiar with. Second, is that the fuel pump is seized from sitting for three years even though it worked fine when I toased the motor. I am sure there is a simple answer, but I am stumped at this point. I have a new fuel pump relay on order.
These are my questions. Is this the correct plug I needed to test the fuel pump with? Is there a list of the correct part numbers for the fuse box relays? Is there anything I have missed before dropping the fuel tank and changing out the fuel pump?
Any help is greatly appreciated.
************* SOLUTION FOUND **************
OK. Here is what i found out.
Yes. That was the correct plug. In testing the yellow wire, the corresponding wire from the plug to the pump is different so just attach your test probe to the corresponding location opposite the yellow wire.
The white fuse/relay is the fuel pump relay and while the white and green are different in numbering/part numbers etc., and of course color and location; they are they same part number when ordered from Mazda and according to the dealer, the white one is the newer relay while the green colored relay is the factory original. There is no test that I am aware of and the dealer did not know of one either.
I took a leap of faith and dropped the tank and replaced the fuel pump. I put it all back together, including the old relays, and it fired right up.
Part of the problem was that the old fuel pump still made a humming noise, verified by bench testing, but no pumping. The new one, a Bosch brand, almost jumped off the bench and had to grab it before it hit the floor.
The motor runs great and after a short test and break-in road test, only got one minor code which was fixed by plugging in a connection that was missed.
Thanks for reading.
I have a swapped the engine after seizing the engine, the cam sensor failed. Never the less, the car sat for 3 years and I just swapped the engine in June 2012. While the car was stored, at a friend's shop, someone hacked the main fuse box and who knows what else. I fixed the fuses, but I am not sure about the relays in the main fuse box. The new engine turns over and I have spark. The ODBII does not indicate anything wrong (other than recent power failure due to battery being disconnected) and the PCM is getting power. The engine will run with manually adding fuel. However, I am not getting any fuel from the tank though normal means.
http://www.justanswer.com/mazda/6a3am-mazda-626-inertia-switch-1999-mazda-626.html
I found what appears to be the fuel relay location according to this post at just answer. When I test the yellow wire with the relay plugged in, I do not get power. However, I get power when I jump the wire at the relay location. My pump does not get power when I supply power directly to the yellow and black (ground) according to the wiring schematic.
In these pictures I show the plug at the rear of the fuel tank and the yellow wire from the relay. In the fuse box, the white relay is the location of the yellow wire and is labled "Circuit Relay." I am stumped. My thought is that I have two issues happening at the same time. The first is that whoever damaged my fuse box by trying to "pry" out the fuses, swapped something or damaged something in an area I am not familiar with. Second, is that the fuel pump is seized from sitting for three years even though it worked fine when I toased the motor. I am sure there is a simple answer, but I am stumped at this point. I have a new fuel pump relay on order.
These are my questions. Is this the correct plug I needed to test the fuel pump with? Is there a list of the correct part numbers for the fuse box relays? Is there anything I have missed before dropping the fuel tank and changing out the fuel pump?
Any help is greatly appreciated.
************* SOLUTION FOUND **************
OK. Here is what i found out.
Yes. That was the correct plug. In testing the yellow wire, the corresponding wire from the plug to the pump is different so just attach your test probe to the corresponding location opposite the yellow wire.
The white fuse/relay is the fuel pump relay and while the white and green are different in numbering/part numbers etc., and of course color and location; they are they same part number when ordered from Mazda and according to the dealer, the white one is the newer relay while the green colored relay is the factory original. There is no test that I am aware of and the dealer did not know of one either.
I took a leap of faith and dropped the tank and replaced the fuel pump. I put it all back together, including the old relays, and it fired right up.
Part of the problem was that the old fuel pump still made a humming noise, verified by bench testing, but no pumping. The new one, a Bosch brand, almost jumped off the bench and had to grab it before it hit the floor.
The motor runs great and after a short test and break-in road test, only got one minor code which was fixed by plugging in a connection that was missed.
Thanks for reading.
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