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JChimbolo
07-13-2013, 05:13 PM
Have this old CRX. Was running. Had a mallory red pump. Fuel injected motor. 1st gen car.

I cleaned the fuel cell, put in some new lines correctly, one out and one vent back. Doing so I saw they had the old pump still in the lines. I removed the old pump, it was not connected, but the fuel ran through it.

Car won't run. There is fuel to the injectors. If I spray start fluid in a vacuum line it starts right up then dies.

Was that old pump doing something with pressure?

Chip42
07-13-2013, 08:01 PM
I'm not super familiar with the 1g CRX but I'm betting there's a safety circuit that looks at the fuel pump circuit to allow injectors. wire the pump back in, dry, see if it starts then.

JChimbolo
07-14-2013, 06:09 AM
Looking on line it seems to be an 1986-87 fuel pump. off the front is a banjo fitting with something called a muffler on it.

Chip42
07-14-2013, 10:03 AM
that's just a pulsation damper, often seen on fuel rail inlets as well. it's not your problem. I missed the part where you said the old pump wasn't connected to power.

check to see that the injectors are pulsing (use a stethoscope or noid) when you crank and verify fuel pressure in the rail, should be 36-41psi. make sure the pump you put on can provide that kind of pressure, many old carburetor pumps flow a ton of fuel but only at ~10 psi. Mallory pumps that can put out needed pressure have "FI" at the end of the part number (i.e. 4060FI, 5110FI). I always use walbro or Bosch in tank FI style pumps. the fuel pressure regulator (FPR) is still there, correct? routing should be tank -> pump -> filter -> rail -> FPR -> return to tank, and the vent is a separate line that ran through a number of emissions valves tot he charcoal can and out. I'm assuming your cell has a rollover valve and a vent outside of the body to atmosphere. that should be fine.

redpepperracing is the go to site for these cars.
87 civic service manual
http://www.redpepperracing.com/technical/v/87Civ-fsm/?g2_page=2
some pages of note:
http://www.redpepperracing.com/technical/v/87Civ-fsm/87Civ-fsm-chap11b/aad.png.html
http://www.redpepperracing.com/technical/v/87Civ-fsm/87Civ-fsm-chap11b/aae.png.html

tom91ita
07-15-2013, 11:25 AM
i am assuming you have confirmed power to the fuel pump and it is running properly. check the fuel pressure at the rail. may be a fuel pick up issue.

confirm the fuel pick up is on the right connection and that the internal hose/pick-up is on/at the bottom of the cell.

in our 1st gen lemons car, the fuel cell pick up line starting "floating" in the cell. chased that issue for a while.

JChimbolo
07-17-2013, 05:59 AM
I took out the foam and cleaned the cell. Pretty straight forward. I can recheck nothing is wrong. In the engine bay, nothing is changed, so it has the stock FPR and hoses.

I don't have any tools to check the fuel pressure, that is a problem, but it was running with the same pump in there now. A MSD 2225 inline type pump.

So it has to be a problem with the injectors or the cell I assume.