I have an 87 gxl I picked up for $600
The car cranks but doesn’t turn over, the fuel pump doesn’t prime when I turn the key to accessory. I wired the pump straight to the battery and it works fine. I tried starting it like that and still nothing. So I figure the relay is bad, but it still doesn’t start. I’ve checked the firing order to make sure it was correct and I have good spark. I’m not showing a check engine light either.
When I checked compression I checked the rear rotor while holding the button and I had 3 consistent bounces near 70psi and then checked without holding the button and had around 115psi overall.

While looking around I found these things and I’m not quite sure what they are and if the should be plugged into something…

Any help or suggestions is greatly appreciated and thank you in advance…

What are these plugs/parts?

 

The fuel pump isn't supposed to run with the key in the 'ON' position if the engine is not running. The fuel cut switch in the AFM disables it for safety reasons. A continuously running fuel pump in a crash is a bad thing. You can prop the AFM door open, or just jump the 2-wire yellow test connector in your 3rd picture.

An S4 does not have a check engine light. Codes must be pulled manually: http://fc3spro.com/TECH/HOWTO/ERRORC...KI/zerror.html

What was the compression on the front rotor?

70 psi per pulse is low. Ideally, you should be looking for 100+ psi with a strong battery, the engine warm, and the throttle open. The schraeder valve must also be removed from the tester.

Low compression = hard starting, rough idle and lack of power.

Picture 1: Test connector

Picture 2: Aux. e-fan temperature switch plug for cars with automatic transmissions.

Picture 3: The yellow plug is the fuel pump test connector, and the white one looks like the test connector that goes up near the pressure sensor. Green plugs are always test connectors.

Picture 4: I don't see anything unplugged here.

Picture 5: Is something unplugged? This is a picture of the pressure sensor.

 

Thank you for the info!

Does the fuel pump prime at all before start up?
Would hotwiring the pump work to at least get it started?

And the car does not run at this point...would you happen to know what is to be expected for cold compression testing?

 

No. The pump only runs when the car is cranking or when the engine is running.

You can force the pump to run anytime the key is in the IGN position by jumping the yellow test connector at the passenger shock tower.

Are you not getting any fuel to the engine at all? Have you checked the spark plugs to see if they are wet?

Note your compression may be low because the car has been sitting, is flooded, etc.