What is it, and what does it do? Here's a post from the Bekkers message board (unedited) -- "Hi every body
Recently i had no end of trouble some times intermittent with my cosworth engine
having low power funny idling carb backfires etc. Mechanics and the like thought it was comp, ezl ign problems etc but could not quite sort it out.
In the end it was EHA unit on the carb. Testing for current flows to the unit with the faulty unit in place created some strange readings making you suspect another cause, but with a
new one in place readings were normal!
Hope this helps anyone"

QUESTION: Would inspecting/replacing this unit eliminate the idle "anomaly" I experienced at a stoplight the other day -- 800 - 1500 rpm up-n-down. Next light o.k. at 800 rpm?

Thanks!

Brian

The EHA is a fuel pressure device the computer controls for emission purposes.
It shouldn't have any effect on idle regulation.
The idle problem you described is common on 16V engines. Use search feature to see common problems.

This reply comes quite late, but Brian, if you are still experiencing a hunting idle, have your lambda cycle checked. It could be that your car is running too lean. I have had a similar problem and it was caused by an inproper air fuel mixture.

The root cause of the problem was actually a faulty ignition coil which didn't produce enough voltage and therefore didn't burn the air/fuel completely. When sitting at a stoplight, this allowed the mixture in the combustion chamber to go into an overrich condition which resulted in bogging and hesitation off the line. But only when sitting idle for a few minutes or while the coolant temp was low.

To compenaste, the mechanic adjusted the mixture lean. This eased the bogging problem, but caused an idle search.

Once the root problem was traced, the mix was adjusted to the proper setting and there has been no trouble since.

------------------
Cheers!

Yen-Hsen Liem
'93 500E black pearl/black leather; 89,000km; 245/45-ZR17 Michelin Pilot SX; 17x8.25 factory EvoII
'93 500E bornit(blackberry)/black leather; 69,000km; european delivery; 245/45-ZR17 Michelin Pilot SX; 17x8.25 factory EvoII
'88 560SL desert taupe/dark brown leather; 89,000km; Euro headlights
'87 190E 2.3-16 black pearl/black leather; 55,000mi; Euro headlights
'70 280SL white/red; 135,000mi (original); factory alloys; Euro headlights

It's been awhile since I've posted -- new job and VERY busy.

Problem solved after my 90k service (@85k miles).

Thanks!

Brian16V