JakeAndBake

Hey all, in the past several months my E55 has slowly gotten worse about cold starting. It’s got 101k on the clock and fresh plugs and wires. At the start of COVID I noticed every now and then in the morning, the car would turn over and crank very strong but wouldn’t start. After removing the key once or twice to try again it would cough to life. No other symptoms after starting. No problems at any point in the throttle range, always feels strong.

It seems to me like it’s not getting fuel at startup and I haven’t heard of this with others so I’m curious to hear any theories or opinions. When I say cold I just mean after sitting for 12+ hours - I’m in south TX so that word can only be thrown around for about a month out of the year!

coupesedan

Poke schrader valve right after the first cold prime to see if you’re getting (any) fuel at the rail

JohnLane

Verify fuel pressure. When you find that it is OK give it the crank position sensor that you should be keeping with the tools to replace it in your 'Oops bag.'

Yes; I suggest keeping a crank position sensor with your car at all times.