Everything seems to be working, but you seem to be getting about 2 mA more than you should. So something is telling the brain to enrich. You should be fluctuating right around zero at hot idle.

What readings are you getting from the coolant sensor? The spec is 2.3 - 2.8 kO at 20 degrees coolant temp, and 280 - 370 O at 80.

If the EHA is leaking, I would replace it on principle.

You might also try richening the mix in small steps and see if that brings the EHA readings down to around 0.

Assume you have checked for vacuum leaks around the injectors, manifold, and other plumbing?

__________________
Chuck Taylor
Falls Church VA
'66 200, '66 230SL, '96 SL500. Sold: '81 380SL, '86 300E, '72 250C, '95 C220, 3 '84 280SL's '90 420SEL, '72 280SE, '73 280C, '78 280SE, '70 280SL, '77 450SL, '85 380SL, '87 560SL, '85 380SL, '72 350SL, '96 S500 Coupe