Cold morning.... Crank but no start.

[Retroman1969]

Well, the Daily Driver '99 Boxster failed for the first time this morning.
It got down to 17 degrees last night, was 20 when I went out this morning. The car hasn't been driven in two days (switched to my Jeep due to flooding rains the last two days).
The car started right up but then immediately died and wouldn't start again.
I'd crank it for about 5 seconds, rest, crank another 5, etc, for about seven or eight minutes before it finally sputtered to life. It blew a huge puff of white smoke when it fired. Running fine now.
It's weird, it was almost acting like an old car with a bad choke (any of you guys over 40 remember starting a car in the winter in the old days?)
I'll have my mechanic do a check on it this week but thought I'd get some ideas from you guys while I'm at it.
Thanks!

[KRAM36]

I would like to here some thoughts on this as well.

My Box did the same thing last week. All I did was a quick pull out of garage, turn off, moved some wheels out, turn on and back into the garage. Next day she did exactly what you described.

Car has run like a champ since, but I pretty sure I'm hearing some kind of pump kick on while at stop signs that I never remember hearing before this.

[dghii]

Sometimes cars are just weird!
My 18 year old backed out of the driveway a few days ago in is 2005 Mustang (5
speed). Once in the street, he put the car in first and the car died like he'd popped the clutch.
The car wouldn't start. For about the next minute, the car would crank but not start. Gas indicated half full. Finally caught and started and he drove off like nothing had happened.

Hasn't happened since.
I just figure some problems that solve themselves are ones you simply log then move on and see if they reoccur.

[Retroman1969]

Yeah, may never happen again, who knows.
If I had to make an uneducated guess: Fuel pump getting weak, fuel regulator has slight leak, water in fuel.....
There has been no check engine light, so I'm going to assume it's not something like an O2 sensor.
The last time it got that cold, the car ran very rough until it warmed up, so there is definitely something about the temp getting below 20 degrees overnight that isn't agreeing with the car.

KRAM: I'm wondering if your sound is your fuel pump? Especially since you first noticed it after the car acted up for the first time.

[jdlmodelt]

Mine has done that too. If you don't let it run for a few minutes and shut it down too soon it will do it. If it has been setting for a week or two it has done it. I find that I have to push the gas pedal all the way down and hold it there while I crank until it starts. They flood and stall and then don't want to start.

[KRAM36]

Originally Posted by Retroman1969

Yeah, may never happen again, who knows.
If I had to make an uneducated guess: Fuel pump getting weak, fuel regulator has slight leak, water in fuel.....
There has been no check engine light, so I'm going to assume it's not something like an O2 sensor.
The last time it got that cold, the car ran very rough until it warmed up, so there is definitely something about the temp getting below 20 degrees overnight that isn't agreeing with the car.

KRAM: I'm wondering if your sound is your fuel pump? Especially since you first noticed it after the car acted up for the first time.

The pump noise I hear is just like when you first start up the car. You will here a slight pump noise then it goes away. I'll pull up to a stop sign and hear that exact same noise. Not every time I stop, but occasionally I hear it.

[Retroman1969]

Originally Posted by jdlmodelt

Mine has done that too. If you don't let it run for a few minutes and shut it down too soon it will do it. If it has been setting for a week or two it has done it. I find that I have to push the gas pedal all the way down and hold it there while I crank until it starts. They flood and stall and then don't want to start.

Yes, it was holding the pedal down that eventually got it started. I'm guessing the big puff of smoke is further evidence it was flooding (it's not the AOS, I had it checked recently).
I've never driven my other Boxster in sub freezing temps, so I don't know if these engines are prone to flooding in such weather (beyond being programmed to give a richer mixture for cold starts) or if it's the failure of a part.
Thanks for the extra input.

[Timco]

My Ranger is notorious for this, and the Box only does it if it was started but doesn't run long enough for the idle to drop to normal from a cold start. With both, pedal down and several cranks. Then it finally catches and seems to idle rough for a second or two.

[thstone]

Originally Posted by KRAM36

The pump noise I hear is just like when you first start up the car. You will here a slight pump noise then it goes away. I'll pull up to a stop sign and hear that exact same noise. Not every time I stop, but occasionally I hear it.

That is the secondary air injection (SAI) pump testing the integrity of the system. The SAI system is part of the emissions package so the ECU commands a test each time the car is started. This usually happens at the first red light or stop sign that you come to.

To execute the test, all of the SAI system valves are commanded closed and the SAI pump is commanded on for several seconds. The system measures the pressure increase thereby validating that the SAI pump is working and that the system does not have any pressure leaks. If the ECU does not receive the pressure increase signal, the ECU will set an SAI error code and illuminate the CEL on the dash.

[woodsman]

A common cause of cold-start problems is water in the fuel tank. Water collects over time (years) and sits on the bottom of the tank (where the pump pick up is). Once below freezing ice forms and blocks the fuel until it's saturated. In climates used to cold weather fuel line antifreeze is used as well as products that eliminate the water. On some vehicles I've owned I used to occasionally fun them down to fumes to get rid of this but doing that in a Boxster will probably cook your fuel pump...

[Retroman1969]

It makes sense that the engine could easily flood if it stalls on startup, especially on a cold day, since the ECU is trying to blow that much more raw fuel in to get a quick start.
I could also see how there could be water in the fuel line that could freeze. At least once this past week I got in the car to find my water bottle partially frozen.
Started right up and idled smoothly this morning.

[2003S]

I had the EXACT same problem Monday morning -- 0 degrees in Chicago, I have less than a quarter tank, and assumed I had a bit of freezing in the fuel line. Luckily Uber was there to get me going...

Unfortunately, I probably killed my battery trying to get her going, and will have to jump it after it warms up a bit...

[Retroman1969]

At least it's looking like it's not an uncommon occourance. Only happened that once so I'm not going to fret unless it rears up again.
Thanks again for the input!