I finished a stock head swap on a 98 h22a, after adjusting the valves and started it for the first time it idled great. However, I now notice a loud valve train chatter (sounds like one very badly adjusted valve click noise, not the whole upper end) around 2500 rpm that goes away above 3000 rpm there is also a mild sputter that goes with the chatter. I rechecked the valves and all were within spec. At first I thought it was a weak valve spring, the odd thing is if I allow the motor to idle up to normal temp the chatter moves up to 3500 rpm and goes away around 4000 rpm.
Since I'm backed up on other jobs so I thought I would bounce this off a few people before I dig into it again.
Thanks in advance.
Since I'm backed up on other jobs so I thought I would bounce this off a few people before I dig into it again.
Thanks in advance.
Vtec does nothing to the timing, all it does is lock the rocker arms so it rides off the higher lift and duration lobes on the camshaft, the camshaft's timing or ignition timing is not affected at all. The problem was the vtec rockers had oil pressure at idle, not enough to engage in on and off causing a popping/heavy valve taping noise when I raised it from idle raising the oil pressure. And the valves that started running off the vtec lobes made the engine sputter because of the low vacuum from the vtec lobes profile at lower rpms.