Forgive me for reposting this from the Tech forum. I hope this pattern sounds familiar to someone with advice to give. I had the fuel pump replaced on my '86 328 GTS and when the car is warm and running, it runs fine. But here is the bigger picture: COLD START - Starts up at once, with foot off the gas and without difficulty but... COLD IDLE - is very rough and will quit without variable gas pedal pressure. Lots of white smoke and smell (?) until it reaches operating temperature, about 5 minutes. White smoke disappears after about 5 minutes. It runs smooth and clean when warm (won't restart easily though) HOT START - very often the engine doesn't catch; long repeated cranking doesn't help; last resort is to crank with gas pedal to the floor for 20-30 seconds --this gets it started. HOT IDLE - is fine and smooth at 1000 RPM. What's the cause and what should I do, please? Background: This car lives at 7,000 feet above sea level in Santa Fe, NM. I drive it infrequently and it sits for long months with a trickle charger. (That can't be helped.) Before the fuel pump was replaced I had a different problem - car would start and idle fine but after running warm for a while the 'slow down' light would come on and the car would lose power. This no longer happens but the new problem arose right away. It's a U.S. model. Any advice/suggestions greatly appreciated.
I had the same problem. Unplug the cold start valve, the small blue plug right side by the top air intake and see if there is any change. it's suppose to inject just the right amount of fuel when starting the car for example when cold a little more than when hot. sometimes it gives to much fuel other times to little when trying the start the car, they work properly for cold mornings or when car is cold but they get old and the valve does not operate so well when the car had drove and stands a while after a drive in my experience. it seems to spurt to much fuel at times causing it to flood and that's why you have crank with pedal all the way down to get it started. hope this helps. cheers Johnny
I get the "white smoke" on start up, too. It looks like steam (water vapor) to me and quickly dissipates after the exhaust system has warmed up. As well as the cold start valve, you may want to look at Birdman's information in the "sticky" about DIY 3x8 work on fuel injectors. Some of your symptoms seem to indicate sticking or dirty fuel injectors. Lew
