Where is my cold start valve located? - PeachParts Mercedes-Benz Forum

zip · #1 05-10-2006, 07:50 PM

Just ordered a cold start valve for my '88 190e 2.3 from Phil(thanks) at Fastlane. Where is the thing located on my car? Thanks.

Zip
greaser wannabe

t walgamuth · #2 05-10-2006, 08:56 PM

it would be on the intake manifold near the air intake from the air cleaner. it looks a lot like a fuel injector. it will have a fuel line and an electrical line. prob have to take the air cleaner or its snorkle off to see it.

tom w

mctwin2kman · #3 05-11-2006, 08:40 AM

Pull the air cleaner assembly off. It is between intake runner 2 and 3 right in the middle next to the head. You will see the four regular injectors and there lines, then dead center bewteen 2 and 3 you will see a bigger injector with a hard line and electrical connector on it. That is the Cold Start Valve.

mbdoc · #4 05-11-2006, 09:13 AM

Haven't replaced a cold start injector for any starting problem EVER!

Only real problems are for LEAKAGE, either into the engine OR for external leaks.

WHY do you think you need a cold start injector.

mctwin2man is correct on the location.

zip · #5 05-11-2006, 10:48 AM

The engine starts and stalls several times when cold but will eventually start and idle at 1100 rpms for 30-40 seconds before the idle begins surging and falling from 1100-400 rpms and will eventually stall. Replacing the OVP with a used unit made the engine harder to start but when coaxed until warm would idle at a solid, smooth 750 rpm but still seemed to hesitate under intial acceleration.

The head gasket has been replaced, plugs and wires replaced. Your thoughts?

Zip

Mike Murrell · #6 05-11-2006, 10:51 AM

I wonder if you have a vacuum leak(s)?

Once the system warms up, things get "sealed" a little better.

One possibility.

mbdoc · #7 05-11-2006, 11:34 AM

The cold start injector operates only when the engine is COLD & the starter is being engaged! ONLY for a maximum of 12 seconds...below 0F.

The coolant temp sensor is the lost likely problem as the computer relies on that input for warm-up.

lkchris · #8 05-11-2006, 12:28 PM

Note how original poster stated "cold start valve" and subsequent posts use "cold start inector?"

The latter term is correct, but it seems there's a possibility of confusion as regards the idle control valve, which is a cold start helper, too.

mctwin2kman · #9 05-11-2006, 03:01 PM

Water Temp Sensor is the name of the part you need. Takes 10 minutes or so to change. That is the symptoms of a bad Water Temp Sensor. It is what tells the CIS-E to enrich for cold engine warm-up and control the Idle to raise it as well. When not working the engine will almost stall and then speed up as the CIS-E Controller senses stalling. It also tells the system to fire the Cold Start Injector as well. When they go bad they tell the engine it is already warmed and ready for standard operation meaning idle of 750RPM and mixture to run stoic.

zip · #10 05-11-2006, 03:43 PM

Jamie,

Fastlane shows several different water temp sensors. Do I want the 4 pin sensor? Thanks.

Zip

mctwin2kman · #11 05-11-2006, 04:46 PM

You have to look at your engine and see what one it is. There is a two pin and a four pin. The two is two individual connector and the four is one larger round one. You get the one that you have now. Mine for instance is the two pin one with the two sealed connectors sticking up straight from the top of the sensor. You can test it before ordering with a standard Volt Ohm Meter. If four pin then you diagonally test, if two pin then just test each pin to cround and get the Ohm reading. When at 80 degrees celcius it should be around 270Ohm if I recall correctly and over 1KOhm when cold. There is a chart somewhere on this site to the exact values, as temp increases the Resistance decreases.

Edit: Found it.

20C 2.2-2.8 Kohm
80C 290-370 ohm
100C 140-220 ohm.