Ive got my fuel rail out and am cranking th motor and all six injectors fire at the same time. Is this normal? I thought they were supposed to fire in two batches of three, the wirint diagram show them as such in the book. Im trying to diagnose an intermittent miss, all the injectors are new, AFM, distributor, coil, plugs, MSD wires, cap, rotor, intake gasket, etc. Checked timing and fuel pressure, valve adjustment, everything is good except I cant get it to idle smooth below 900rpm.

 

ya they are all supposed to fire at once its a batch fire system. I don't know the advantages but ya its normal! did you listen to all your injectors and make sure they all sound the same? I had the same problem I had checked everything and couldn't figure out the miss/hesitation and mine was just a fuel issue like something was clogging the head....

 

I pulled them all out of the intake to make sure they spray, because a few of them were pretty quiet. They all seem to spray fine, I just cant get this thing to idle like I want it! Oh well, a 950rpm idle is acceptable i guess. anyone know where I can get them flow checked? The only other thing I can think is that my valve adjustment skills arent that great. It's PITA on a hot engine, and the oil between the cam and rocker plays havoc with the accuracy of the feeler gauges.

 

Mine were in need of cleaning and testing, and I used this service:
http://stores.ebay.com/Mr-Injector_F...QQftidZ2QQtZkm

I bet if you contact him for a test-only, he'd have a fair offer. The turnaround was fast, service was professional, price was competitive (he included the cold start valve, too), and he did before and after flow tests (sends the prinout(s) back to you). I couldn't find anyone close enough to me locally not to have to do it by mailorder. There're a good number of places that'll do it on a send-away basis.

Dave

 

It wasn't until 1988 that the Z got two batches of 3 firing injectors.