I had read with interest a few earlier posts about cold idle problems in the 240 turbos--especially since we were having similar problems with my our car. Symptoms were the car running extremely rich when cold, with idle fluctuating from 900 to 1500 rpm. Black exhaust when pulling away from rest, really smelled of gas when cold--even my son's friends noticed it. Gas mileage was pretty crappy too--about 15 mpg.

I ran the checks in the Bentley manual but came up empty every time. Had the car in at our local dealer yesterday (AC recharge after 134 conversion) and asked my friendly master tech to take a look . . .

Well, it took him two hours, but he found the problem: an intermitent failure in the delay valve associated with the cold acceleration enrichment system. It would dump the vacuum in around one second as specified--but only the first time--then it held the vacuum indefinitely, leading to excessively low control pressure until the car was completely warmed up.

We removed the delay valve completely (until the new one comes in, about $30)--pretty reasonable compared to the cost of a new pressure regulator, even with the 2 hours labor for the trouble-shooting.

Bottom-line is that the improvement in drivability is huge. Sometimes a slight stumble when pulling away when cold, but hardly noticeable compared to before.

Hope this helps.

Regards,

Steve A-