Hi guys,

I just need your experience on this idling issue I have. It's more a slight shake than a stumble. As you might have guessed I replaced 1 steel injector that fouled up when I previously had a burnt valve with a brand new brass kind.

When mixing old(steel) and new(brass) injectors, is the opening pressure difference great enough to cause irregular idling? I'm thinking that since the entire injection system has the same pressure from distributor to injectors, new injectors mixed in with the old actually causes fuel starvation for its assigned cylinder.

My issue is there at start-up then goes away during warm-up, but comes back at WOT. Vacuum lines have been checked and replaced those that needed it. Ignition parts checked/replaced. Air/fuel mixture at 50% with a new O2 sensor.

Thanks in advance.

bpaz_ph
'87 190E 2.3 8V