any ideas on why my injectors at nbr 3, 4 and 5 wont fire but the others do? I can get the engine to start/run but it's rough. Pulling the connectors from injectors 3, 4 and 5 don't do anything to affect the engine while running. pulling any of the others will cause it to shut down.

I thought I had bad injectors (they are all new) so I pulled the 3 that arent working and replaced with 3 new ones. No chnage.

I'm perplexed and out of my skill set here. It's got to be something simple?

any ideas amigos?

1983 280zx non turbo..

 

Are the injector connectors corroded? Loose? Burnt?

The first thing to do is get an injector noid light to make sure all 6 injectors are getting power. If some are and some aren't, the injector harness is probably toast (FricFrac sells a harness fix kit).

If all 6 are receiving power, check fuel pressure. Also, mix and matching injectors doesn't always mean they will work. We've discussed in the past ways to rig up an injector test station.

 

thanks for the tips. All the connectors look fine, fit snug, arent burnt so I'll check out the tester you mentioned. otherwise it's going on the trailer and off to Awesome Z on Monday..

 

another observation, the green light on the ECU is on/off intermittantly while engine is running. Should it be on continuously when running?

I have checked everything else except I have not made or purcahsed a noid light yet.

 

I have the same problem how did you fix it