190E low idle when cold - PeachParts Mercedes-Benz Forum

pentoman · #1 11-11-2004, 01:12 PM

Hey all,

Can we have a very simple explanation of the cold starting procedures of the engine here please?

There's a lot of posts if you search, but it's heavy reading and very confusing. All I know after reading it is:

There is a water temp sensor, its readings measured with a multimeter should be:

temp reading
-20 15.7 KOhm
-10 9.2 KOhm
0 5.9 KOhm
10 3.7 KOhm
20 2.5 KOhm
30 1.7 KOhm
40 1.18 KOhm
50 840 Ohm
60 600 Ohm
70 435 Ohm
80 325 Ohm
90 247 Ohm

Apart from that, I know there exists something called an EHA (Basic explanation of what this does?) which can be adjusted.

and a 'cold start valve', is this an actual valve? Is it part of the EHA? does this enable 'cold start enrichment'? Should you get a higher cold idle even if your tuning is way out?

This is for M102 190E, 200E, 230E four cylinder (and M103 six cylinder?)

My car when cold idles at about 750rpm (too low), stumbles, and will stall very easily. It actually starts fine (after 1-2 seconds), though is best of with a bit of gas.

I've had it tuned up right, but it just seems the part that gives me a decent higher idle when cold is missing.

Tested my water temperature sensor, it reads: 8 KOhm at cold (5 degrees air temp) and 600 Ohm engine warm (80 degrees engine temp on interior guage), which seems about right. Unplugging the plugs from this sensor makes the engine stop, so it seems something is reading the sensor. The question is, shouldn't it be making the engine idle higher when cold?

Russ