1979 Z hesitant at initial acceleration

[Kevin Livesey]

I need help with my car. I started a new thread as the other was becoming too long.

My main issue is that the car underwent a 7 year restoration. The engine was dismantelled, fitted with new rings bearings and gaskets. Ever since it's been reassembled it is hesitant to accelerate from any RPM low or high and hot or cold. It idles really smooth and is also smooth at any constant RPM. It also idles high when cold but fine when hot. I have already swapped out the coil, plugs, leads, distributor and cap, checked all the vacuum lines, changed the thermotime and water sensors, changed the ecu, cleaned all the electric terminals and adjusted the idle and mixture screws. All of this made no difference to the hesitation. i've also installed a new fuel filter.

[ZCurves]

Questions to elicit some thought...

1. Is the transmission Auto or Manual? An Auto Trans could have a Torque Converter or "Stall-Out Issue"
   
2. Have you checked the Fuel Regulator?
   
3. Does it hesitate when it is NOT under a load (In neutral)?
   
4. Does it "Pop" when you give it sudden hard acceleration?
   
5. Have you replaced the exhaust system? (Clogged CAT / Bad O2 sensor.)
   
6. Have you tested or changed your AFM?
   

It still sounds like a Vacuum Leak or Timing to me...

That is all that comes to mind without further cross examination by our fellow Zed Heads.

Edited February 4, 2010 by ZCurves

[Kevin Livesey]

I found the problem to be gasket material in the injector orifices of 2 cylinders partially blocking them. Seemed to run fine after being cleared out.