ka24de injector problems

[portageedemo]

I rebuilt the top end of my 91 240sx and when we put it back together, no gas to the motor. We have pressure to the injectors, but nothing going into the cylinders. When we pulled the spark plugs and dropped some gas, it hit a couple of times, then nothing, so timing is on. I can't find any wires not connected. The only thing that I am thinking is that I got the vacuum lines reversed on the back of the motor. Would this cause the injectors to not work? This is about to drive me crazy. Thanks in advance.Ken

[sx moneypit]

The vacuum lines have nothing to do with that.Sounds like your injectors are not firing.Double check your wiring harness.

[portageedemo]

We have been checking the harness and everything else that we can find. That is why we were thinking the vacuum lines, because one line goes directly into the end of the injector and thought that maybe if it was hooked up wrong, that it was causing something to stop the flow of gas, which would cause a vapor lock condition. The Chilton book sucks for this car. Is there some relay or fuse that runs the injectors? We found the fuel pump fuse and other fuses, but nothing on the injectors. This is my son's car and he comes back from college in a couple of days, so I need to figure this out, so I can get back to the overhaul on my Honda Passport.ThanksKen

[rioredstang]

Vacuum has nothing to do with fuel flow. The injectors are not pulsing. You need to check the cam sensor that is located in the dist. This sends signal to the computer to control firing of injectors. Throw the chiltons manual away. Look in the factory service manual, use the link below. The FSM will tell how to test the cam sensor. You can look at wiring diagram to make sure you have power and grounds.

http://www.nicoclub.com/FSM/240sx/91-94/

[portageedemo]

Thanks for the reply and access to the FSM. Checked the injectors like it says and they are clicking. Pulled the plug and got it to TDC and have a spark. The one thing, I have the fuel in line connected and then we took off the return line and when we turned on the key, their was no fuel coming out of the return line. Should there have been? I spent 2 hours going over the FSM and just could not come up with an answer.ThanksKen

[sx moneypit]

You need to check your fuel pressure, it should be 36 lbs with the vacuum hose connected and 43 lbs without it connected to regulator.

[rioredstang]

Yes, there should be some fuel in the return line. This is a sign the fuel pump is weak or not working. Check fuel pressure.

[portageedemo]

Thanks guys, I will give it a try tonightKen