W124 300TE-24 cold idle problems
 

Hi, I bought myself a 1991 300TE-24 Auto estate a few weeks ago. I'm very pleased with it, but there are a few issues that need looking at, one of which is the idle after a cold start.

When started from cold, it will start quickly but cannot idle on its own; I have to keep blipping the throttle or the revs fall and the car will stall itself, there is also a smell of petrol from the exhaust when it is started from cold. After a few minutes the car idles fine and the petrol smell goes away.

Also, when I try to start it warm, it takes a few seconds to start. The starter motor turns normally but it just takes longer to fire, though once started it idles smoothly and runs fine.

Can anyone help?
Thanks.

If you have the 104 engine in a 91 wagon, that is a rare bird. Is it an HFM setup or a CIS setup, diagnosing your problems are quite different between the two.

That would be a 104.980, so it is not HFM or DIS.
Same a 300CE 24.

It is the M104 engine with the KE-Jetronic (or CIS) injection sytem.

Usually u can start by changing the ke-jet control relay located near the injection ecu behind the battery, it’s a relay of considerable size and has a metal case with a red plastic top (as I recall)