FigurativeGarbage

I installed EFI-rated fuel hose and filter, but still had to build the pump relay and resolve my switched ignition and constant power wiring. I added a 125-amp terminal fuse at the battery feeding a positive bus bar and switched the starter relay wires over. I also installed a ground bus tied directly into the battery ground system. The VATS bypass is connected to the same switched ignition source. I’m using the GM VATS Bypass Module for LS1 and LT1 from Timers. After some troubleshooting with the multimeter, I found a missing PCM ground connection. Once that was corrected, the fuel-pump relay clicked and the pump finally hummed. I rented a fuel-pressure gauge from O’Reilly Auto Parts. It connected easily to the Schrader valve on the fuel rail. The pressure came up into the low-40 PSI range and held. I installed a Dakota Digital pass-through speedometer sensor at the transmission as well. This allows the PCM to receive the electronic vehicle-speed signal while keeping the original mechanical speedometer cable and factory dash functional.

I've written some stuff on an early 90's 3.4L Camaro engine. I'm about to pick up the project again after a year on the backburner. I made wiring diagrams and such.

Seems to have fixed pump/baffle issue. I haven't seen anyone else do this, nor has it been suggested. I hope it works. In the image below, cut the sender guides on the tank wider (at 7 and 11 o'clock). At this orientation, the pump won't press into the baffle wall. I also was able to get the sock on with one hand in the tank. Had to walk away from it twice before I had an aneurysm.

Looks like I have a common issue: the baffle in the tank is in the way. However, it seems that if you turn the sender just a few degrees to the right, the pump will point straight down and sit in the baffle. This would require doubling the space for the guide tabs, but it seems easier than cutting the baffle (and compromising its function) getting a new tank, bending the sender, or getting a new sender. My hope is the gasket under tension keeps it aligned. It seems no one else has done this in the other threads. Also, the fuel gage is in the way when installing, so I have to partially disassemble the sender and reassemble it with one hand it the tank. I can do this, but getting the sock on the pump with one hand feels like a carnival game.

Looks like I'll go for the MTS JPSU-6P4.0. Seems like it will provide enough flow and PSI for the 3.4L. https://www.mtscompany.com/sendingunits.htm $39? Its like $65-$160 everywhere else: https://a.co/d/hePOZeq

Dropped the tank and pulled the sending unit. As I suspected, there's a hole near the rear grommet that is likely the source of water contamination. After I get a new tank, I need a fuel sending unit that will deliver 36-50 PSI to the Camaro engine. I prefer to do it in tank, but I'm not interested in figuring out a complicated custom system. I may do in-line so I can get this fired up this year. I'll need new fuel lines for the pressure in any case. Open to thoughts.

Spent some time this weekend sorting the original engine bay wiring a bit more. There are still several mystery connections to resolve (hanging outside of the cabin in the pic below). I removed the auxillery lights and relay for now. I also removed the fuel pump and what I think was the B+ latch relays as they look pretty corroded. I ordered a relay box and bus bar to help clean things up. I'll also relocate the electric fan relay the previous owner installed. Frustratingly, I found water in the passenger side cabin. I see in other posts this isn't terribly uncommon and is likely either the hood hinge seal or the blower/heater seal. I'm not wild about pulling the dash right now. Goal is to try and get the motor started soon.

It has those sections, for sure, but they don't have the illustrative diagrams that I found helpful as an amateur (pinouts, harness routes, etc.). If I'm wrong, let me know what page or upload (if you have have a chance). For example, white, yellow, and green run to the axle and I am guessing they are the 4wd actuator. Identifying these will take some time, but I suspect they are no longer necessary unless they run to the gauges. Points if you know what this is.

I removed the starter solenoid because the new starter has an attached solenoid. I'm thinking I'll keep the ignition relay. I removed the ICU/distributor (between the original fuses and alternator). The standalone wiring harness is largely thinned save for figuring out the C### connections. I need to clean up the remaining original wiring a bit more (A/C related, I/P to engine connectors, etc.). It is harder to find information on the 2.5L Comanche; the service manuals are not as thorough as the Camaro manuals I've been using for the engine (wiring diagrams for the instruments, headlights, etc.).

I can't seem to download this (link is a blank page). Can anyone re-upload it?

Cleaned up my hand-drawn diagram on Lucidity. I believe I found one solution to this set up: a VSS dual bypass (Dakota Digital SEN-01-4280). This allows the mechanical signal to go to the dash and converts an electronic signal to the ECU. I believe the B28 Buffered Speed Output sends to the dash and therefore can be removed. I'll next make a list of the C100-230 wires that need to be resolved (fuel pump relay, etc)

I'm currently working on a standalone ECU harness. I’ve de-pinned around 17 wires from the ECU connectors. Most of these were related to automatic trans and AC functions, which are unnecessary for my standalone setup. (not my photo, but used for initial reference) (one of the Camaro manual diagrams) I've been looking at connectors C100, C210, C220, and C230 that connect to lights and the body harness. Example: the C220 alternator connector powers the dash. I have a GM VATS bypass from Timers. I need to figure out speedometer and fuel relay wiring. (The C220 only has two wires in it right now, and matching connector. I'll need to figure out the clutch anticipator.) I also discovered a mystery component with brown and black/white wires that seems to be tied to the oil level sensor area (it has some kind of recessed button that clicks when pressed). The actual oil level sensor connector nearby has two-black-wires. I'll trace the wires back for both if I have to. (Manual reset button? Diagnostics? Kill switch? Jetpack handheld ignition control?)

I got them from my neighbor. I'm sure you're right. Appreciated, but its okay. The original ones are on now. Mostly an aethetic thing anyways.

Looking at the clearance, I think modifying the pan was unnecessary. Maybe other the other builds noted the issue had different set ups. See the attached photos; one may appear upside down, but you can see there's a great deal of clearance. In hindsight, I would have installed the engine without a pan and check the clearances after.

It's okay, they were aftermarket aluminum valve covers. I kept the original covers just in case. Glad I did.