1988 420 SEL, idles rough during warmup.
Runs fine at operating temp.
I checked fuel pressures with coolant temp 30deg C and found system pressure of 95 psi and lower chamber pressure 88 psi. Seems ok.
I checked the coolant temp sensor and it seems to be working correctly. 1.4k ohms at 27deg C; 280 ohms at 85deg C.
I unplugged the EHA and the idle dropped slightly and did not improve.
Checked the resistance across the terminals of the EHA and found 19.7ohms, within specs.
I read in another thread about adjusting the EHA to change the amount of enrichment during warmup. Anyone know something about that?
Any thoughts on what I should try next?

Thanks,
Jim