PeachParts Mercedes-Benz Forum - View Single Post - 300E with cold-startup problems/low idle

pawoSD · #8 11-23-2008, 10:31 PM

I already made an order online earlier today for essentially all vacuum tubes on the engine, some are visibly in bad shape....so why not replace them. I also bought a new OVP relay....since it can cause so many issues....if its not bad then I'll have a spare.

Cold start issue on this car is defined as: Real cold outside and it hasn't been started overnight, or for a long enough period that its back to outside temp. Starting the car consists of cranking for about 10 seconds, the first 4-5 it doesn't do much but rotate, then it begins to catch and sputter, then by 9-10 seconds its going on its own and you can let off the starter. However, you have to let it do its thing for a couple mins (1-2 mins) as its idling around 450-500 and if you give throttle it dies instantly. After those 2 mins of low idle, it will respond to throttle and is fine, and you can't stall it....despite a very low idle. In driving when warmed up the idle varies anywhere from 500 to 700, in park all warmed up it stays around 600-700 nice and steady.

When the car is warmed up (has been run within the last hour or so) it will start pretty reliably, might take two tries, but only a couple seconds of cranking. Then it runs but idles low (500) as usual....but will not stall. It has never shut off or stalled while driving.....it does feel like it misses sometimes.

When its real cold starting it does feel like its missing on a cylinder or two, and it shakes (but not every time), this smooths out within a minute or two.

When I get some time to actually disassemble it a bit over the next couple days I'll be able to test some stuff and give a good visual inspection to all components. I'm sure it needs hoses/tubing replaced, some are bandaged with tape.

The fuel pump runs properly for a couple seconds and then shuts off when the key is put to run.

When running warm it runs very nice, and it has good performance....it will rev all the way to red line and pull hard.