Date registered: Aug 2005
Mentioned: 0 Post(s)
Quoted: 0 Post(s)
RE: ML 320 will not start in HOT weather
I have the same problem with my 1998 ML 320. After driving it for a while (engine reaches normal operating temperature of around 80 deg C) and then turning off the engine for about 30 minutes to an hour, it will not start. this happens about once every five attempts to start. The engine does not appear to be getting any fuel (like a vapor lock). After trying to start it a few times and then letting it sit for 5 to 10 minutes, it starts up without any hesitation. I always have to let it sit for 5 to 10 minutes after the first attempt to start it. Otherwise, it runs smoothly so I do not think it is a fuel pump or fuel filter problem. It could be fuel pressure. However, why do I have to let it sit for 5 to 10 minutes before it will start. And when it starts it is as if nothing ever happened. It does not cough or stutter. I do not think it is related to the environmental temperature but instead to the engine temperature (normal hot temperature of 80 deg C).
For your information, I had a "Check Engine" light caused by "Fuel Trim Malfunction in Bank 1 and 2 which I fixed by replacing the Mass Air Filter or Air Mass meter. No more error codes or check engine light however the start problem still persists.
Any help would be appreciated. I will let you know if I solve the problem.