Well, it's almost summer and my annual 2005 TB EXT electrical problems are back. 4.2 straight-six with 4WD.
Over the last 3 years, I've been getting increasing multiple-cylinder misfires. Last year, I replaced all ignition coils and plugs. This year (in the last two days), I replaced the PCM, battery, ignition switch and alternator.
PCM passkey confirmation worked, so I know the new PCM is functional. But, when I try to crank it, it never fires up and it blows the PCM 1 fuse (#28) every time.
Also, I don't smell any gas, so I doubt the fuel pump is sending. All of which sounds like a bad fuel pump and/or fuel pump relay, and/or a short somewhere in the ignition harness. However, if the ignition harness is shorting somewhere, that can blow the PCM 1 fuse, which shuts down the fuel pump.
I've had problems in the past with coil connectors melting, so that's my first suspicion. Ideally, I'd like to replace the whole ignition coil harness, just to get that out of the way...unfortunately, I can't find the ignition coil harness for a 4.2L 6 cylinder. There are so many varying descriptions online (some of which say that specific harness is discontinued), I don't know where to find it.
Can anyone just POINT ME to the 6-cylinder ignition coil harness for the 2005 TB EXT 4.2? Once that's out of the way, I'll pursue the fuel pump and fuel pump relay. Thanks in advance!
Over the last 3 years, I've been getting increasing multiple-cylinder misfires. Last year, I replaced all ignition coils and plugs. This year (in the last two days), I replaced the PCM, battery, ignition switch and alternator.
PCM passkey confirmation worked, so I know the new PCM is functional. But, when I try to crank it, it never fires up and it blows the PCM 1 fuse (#28) every time.
Also, I don't smell any gas, so I doubt the fuel pump is sending. All of which sounds like a bad fuel pump and/or fuel pump relay, and/or a short somewhere in the ignition harness. However, if the ignition harness is shorting somewhere, that can blow the PCM 1 fuse, which shuts down the fuel pump.
I've had problems in the past with coil connectors melting, so that's my first suspicion. Ideally, I'd like to replace the whole ignition coil harness, just to get that out of the way...unfortunately, I can't find the ignition coil harness for a 4.2L 6 cylinder. There are so many varying descriptions online (some of which say that specific harness is discontinued), I don't know where to find it.
Can anyone just POINT ME to the 6-cylinder ignition coil harness for the 2005 TB EXT 4.2? Once that's out of the way, I'll pursue the fuel pump and fuel pump relay. Thanks in advance!
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Shouldn't be too many differences. Rear HVAC wiring, 3rd row seat headliner lights, and 3rd row seat window switch wiring to the overhead console should really be about it. I'd imagine the underhood wiring should be the same. If the harnesses plugging into the fuse blocks are pinned differently, you could easily re-pin them, since you've got your original ones to compare them to.
