fuel injector problem?

[teletom]

SO here is my problem, I had one black fouled plug in my 77' datsun 280z and it seemed as though i had a dead cylinder so i checked spark on all plugs and compression tested all cylinders and got 120 across all of them a couple were about 125. so i assumed it was my fuel injector just dumping fuel and fouling the plug sop i got 6 rebuilt injectors from BAP and installed them this morning, when i started her up she ran even worse. Now i have centralized the problem to the 3rd & 4th fuel injectors. When i take out the spark plugs on these two there is no difference and i checked the spark for both and when i take the fuel injector connector off there is also no difference in both. I used a circuit checker to check the fuel injector connection and i also tested them by using them on different injectors. So I finnaly decided to put back on an old injector onto the 4th cyl and removed the new one and i still have the same problem. I also tested the new injector that i removed to see if it was firing and it was. Now i'm stumped and need any help you guys can offer! thanks much

-zane

[Zed Head]

I used a circuit checker to check the fuel injector connection and i also tested them by using them on different injectors.

What were the results of your tests? And where is ZUPPAN?

[teletom]

It lit up plus i attached the two connectors to different injectors and it made them spit so i know they are working. Haha zuppan is my last name not sure how i wound up putting it for my location.

[hr369]

injector connectors should be replaced or the very least cleaned with a good electrical contact

cleaner. did you test your injector with a full 12v from the car battery

[Zed Head]

It seems like the tests show that the injectors are okay but the connections aren't. There are two sides to the connection - power supply, and grounding at the ECU. You can check the connector pins with a voltmeter. We just had a big discussion about in another thread.

You really need to switch from a phone to a computer to get the good direction on what to do. It's all in the Engine Fuel chapter of the FSM.

http://www.classiczcars.com/forums/fuel-injection-s30/52066-no-start-fuel-injectors-not-firing-1978-280z.html

Datsun Service Manuals - NICOclub

[FastWoman]

Injector Connector Kit 6pc Datsun 280z 280ZX 300zx | eBay

My advice would be to buy a total of 11 connectors -- 6 for the injectors, 1 for the thermotime switch, 1 for the cold start injector, 1 for the coolant temp switch, 1 for the accessory air control heater, and 1 as a test connector you can throw in with your tools. Contact the seller to ask him to put a kit together for you. He did that for me.

Edited April 18, 2014 by FastWoman

[siteunseen]

I bought those ^ connectors too. It takes a while to do but it's worth it. I had 1 or 2 old ones that would just fall off the injectors, cracked pretty bad.

[ZCurves]

I bought a set of those replacements years ago and grafted them into my harness. They work well, just make sure to get the boots as well. Now If I were to do this all over again I would choose the connector with the Quick Release spring rather than the traditional clip. The would no doubt make service/inspection a much easier process.

Injector Connector 6pc Kit Quick Release EV1 Datsun Nissan 280z 280ZX 300zx Z31 | eBay

[FastWoman]

^^^^ Oh yeah! I wish I had those instead!