Context
Did some wrenching on the car after discovering the previous owner bypassed the throttle body coolant and had a hose clamp securing a vacuum cap on the rear iron nipple and back of the water pump. This was my first time removing the UIM. Since I had to drain the coolant anyway I figured it was a good time to install the FC fan switch. When it came time to re-install the alternator, the wire came in contact with the engine hook and I saw a spark...

Diagnosis
After putting the car back together I went to burp the system, the car cranked but wouldn't start. Looking at the PFS, my FUEL was highlight as out of range. Fuel issue is confirmed by checking my FPR when the key is in accessory mode, there is no fuel pressure. I can manually prime the fuel pump with a paperclip and the Diagnosis box.

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I have visually inspected the fuses and doesn't look like any have blown so I'm curious what the issue could be. Any pointers would be greatly appreciated.

- Alex

 

Not great with electrical issues myself, but would still suspect a fuse. I might use a multimeter to look for power on both sides of the EGI...box just aft of the battery.
Deleting AWS and the t-body coolant line was pretty common but there are better ways to do it. FWIW I still use that line for my aftermarket temp sensor...just looped it from front to back.

 

I'm 99% sure that fuel voltage is actually for the fuel temp sensor. As far as the pump not priming with the key, you will have to start with the fuse boxes. Because it still works at the diagnostic box, it verifies the circuit is fine but something that triggers it, is not. This shouldn't be too difficult to find. Just go one fuse and relay at a time starting at the battery fuse box, then go to the bigger one, then to the interior.

Valuable lesson learned though. Always disconnect the battery when working around the alternator or starter.

 

Could some explain why I should start with the fuse boxes? If a fuse was blown, wouldn't the jumpered diagnosis box not prime the pump? My next move would've been to check the fuel pump pin on the PFC, but want to hear what others think.

 

the diagnostic box bypasses the fuse box. its a circuit all on its own. it goes direct from battery power to whatever component youre jumping. seems like you have a handle on it though. good luck, check back in when you fix it

 

I was able to diagnose the issue over the weekend. Fuel Pump relay wasn't clicking on. I swapped the AC relay with the FP, and that fixed the fuel pressure issue but the car wouldn't crank. After some research, I decided to unplug the security system relay and jump it. Car was able to start just fine.

Anyone have suggestions for what to do with my security relay? I believe a PO installed an after market security system, unsure if that affects my situation.