key off and still running, weird!!! but not always - PeachParts Mercedes-Benz Forum

Basstrip · #1 01-10-2011, 04:30 PM

Here we go.. 92 300SD some times turns off mormally, some times takes a few seconds and some times I have to push lever. I been doing some research on this wonderfull site. test perform-, engine off pull off hose to shut off valve at IP push sutt off lever plug hole at valve and lever stays down until pull plug off. check hoses for visually leaks every looks tie, also check brown hose for oil and the shutt off valve as well, no oil. look under dash by sterring colum and could not find the ignition valve with two hoses connected to it, where is this valve that some people mention on this site? I do know there is a relay switch the sends a signal to activate shut off valve, how to check this relay for testing? Also when is cold starts righ of way after heating glow plugs, then warm do not want to start. I have to heat up plugs in order to start even when warm.. Well gys hope some have some ideas on this issues. Thank you and lets have a wonderfull year

TX76513 · #2 01-10-2011, 05:22 PM

Do you have a Mity Vac? Check your shut off valve for a bad/weak diaphram. Common problem, easy fix.

Diesel911 · #3 01-10-2011, 09:18 PM

If your Ignigion Key Tumbler was a clock it looks like the other Vacuum Valve is in the 10 O'clock position.
You may need to pop out the Instrument Cluster in order to see it; if you are able to do that on your year and model.

Basstrip · #4 01-11-2011, 11:59 AM

I did check the shut off valve by push down lever and plug the hole on top of shut off valve, lever stay down until realease plug, also check for oil on the hose and was clean. Now I need to know how to check the relay, and need to learn to test the valve at the ingition switch, also need to find out how to get it the ignition switch out.