My 82 400i just arrived the day before yesterday, and I've been having a blast driving it, and discovering its quirks. Today, it's home in the garage with a dead battery, since I can't get it to start. It turned over fine, and a couple of times it even sputtered, but still no start. I can smell fuel now, so I'm sure it's flooded. Once I get the battery charged up, what do I need to do? Is there a knack for starting a cold 400i? I learned that to start it warm, I need to push the pedal almost all the way to the floor, and it starts right up, and idles fine. Ideas? TIA, Kraig
Start by taking the plugs out and cleaning them......as for starting procedure...... just get in and turn the key 400i's are one of the easiest of the proper V12 cars to use
If the ambient temp is quite warm (T shirt) , and you've missed the first few splutters of life, it can help if you un plug the auxillary cold start injectors. This reduces the tendency to further foul the plugs. These are a blue plug on the plenum chambers.
Be VERY careful with a dead battery. DO NOT jump it if you have the original dinoplex ignition installed you'll cook it right away. Disconnect the battery cables, charge the battery, then reconnect. You should not have to floor it when it is warm/hot. If you need to do this then the large relay that controls hot start injecting is either bad or not making contact. Not making contact is a common problem. The relay is so big that when you hit a bump it comes lose. Fold the relay board back, try to start it when warm/hot. You'll hear the relay click multiple times as you're cranking it over. It is the tall black relay on the far right side of the relay board and is the largest relay on the board.
Cold starts on my 400i are almost instantaneous with just the slightest depression of the accelerator pedal. Hot starts are quickest with a little bit more pedal. Although it does start with the foot off the gas, its faster with a little bit of pedal. One of the coolest things about the V12 is the way that it just explodes into life when you turn the key. Gives me goosebumps every time! I would echo Dave's statement about charging the battery rather than jumping the car with a dinoplex. If you are stuck on the road with jumper cables, its better to just hook up the two cars and let the running car charge the dead battery for a few minutes without trying to start the car. Unless the battery is on its last legs or somehow got run down really flat, it should muster enough of a charge after 5-10 minutes to get a restart. If you have a battery shutoff switch that obviously provides absolute assurance of protecting the dinoplex, but just letting the other car charge your battery shouldn't do any harm. You could probably clean the plugs but they should be okay if they have had time to dry off from fuel soaking. Good luck John
Thanks to all who replied. I've read other posts about not jumping the car, so I had it on the trickle charger, and now it's fully charged. I let the excess fuel evaporate over a 24 hr period, so hopefully this will do it! Looks like I have to do some work on the injectors. Kraig
