Crank-but-no-start I need your help :)

[rkstar9]

Hello
I left my z sitting outside for 3 weeks in -10F while I was on vacation,
Today I tried to start it and it cranked slowly at first but later at a pretty good pace and was not able to get it to go.

I have taken the following initial step:

• Added 2 gallons of new Gas (tank is now 3/8 full)
• Unplugged MAF. made no difference.
• Cranked for over 45 seconds as you will see on video
• Used a jump start battery in addition to letting it charge for 30 min. Crank seems to be fine
• Read codes with INPA no errors are present.
• checked battery terminals which appear fine, battery is about 3 years old but seems to crank like a champ? I am unable to verify date on battery as I can not see any markings. (see attachment)
• I smell uncooked fuel after cranking and hear what I think is the fuel pump when switch is turned.
• fuses under glove compartment appear to be fine, all tho I did not pull everyone just the ones that are related like ignition, ews, dme etc.
• Both keys have the same issue.

I went over this thread:
No start
and this one Ignition/start failure

It seems to crank and go faster and faster until ultimately it chokes itself and dies. until it starts over again.

obviously some of the things I tested like the fuses and the fuel and the battery can be further tested, also I don't know if there is any spark but there are no codes or cel. The car used to start perfect every time, also the coils where replaced 30k miles ago at the dealer. This is a 03 z4

Thanks a lot in advance

[StickMon]

Flooded?

Anybody know an easy way to cut the fuel flow?

The last cars I had flood in sub-zero weather had throttle-body injection.
The solution was to unplug the fuel injector and crank it until it dried out.

[mtrhed]

Probably.
Plugs are most likely fouled at this point. Maybe remove fuel pump relay see if it fires? I used to have to do this with my older BMW's along with letting some unmetered air in when seriously cold out.

[the dink]

Is it stick shift car?. If so have someone pull start you in second gear. That thing needs more cranking speed. I noticed your temp was 44 degrees, Mine cranks a lot faster than that at that temp. Battery or starter not right. I know it should still start but probably flooded like others have stated, that's where the pull start will blow out the excess fuel.

[rkstar9]

Originally Posted by StickMon

Flooded?

Anybody know an easy way to cut the fuel flow?

The last cars I had flood in sub-zero weather had throttle-body injection.
The solution was to unplug the fuel injector and crank it until it dried out.

Thanks this might be it, I was reading codes with a new scanner before I let the car sit, probably turned the key without igniting the car too many times.

I pulled the dipstick out and did not see any signs of fuel mixed with oil so it's probably minimal.

Originally Posted by mtrhed

Probably.
Plugs are most likely fouled at this point. Maybe remove fuel pump relay see if it fires? I used to have to do this with my older BMW's along with letting some unmetered air in when seriously cold out.

I see 2 fuses for the pump, so do I just pull them out and crank it ? how will I know when the fuel is dissipated?

Originally Posted by randyf

Is it stick shift car?. If so have someone pull start you in second gear. That thing needs more cranking speed. I noticed your temp was 44 degrees, Mine cranks a lot faster than that at that temp. Battery or starter not right. I know it should still start but probably flooded like others have stated, that's where the pull start will blow out the excess fuel.

It's a stick shift, I will work on getting someone to push me then.


Additionally, the car has been throwing codes for the thermostat value below threshold, about 4 weeks ago I found the coolant was almost completely empty and the engine was overheating, but the low coolant light did not come on.

I read on another forum where a faulty coolant temperature sensor can cause the engine to flood, but it wasn't explained why.

[the dink]

Additionally, the car has been throwing codes for the thermostat value below threshold, about 4 weeks ago I found the coolant was almost completely empty and the engine was overheating, but the low coolant light did not come on.

I read on another forum where a faulty coolant temperature sensor can cause the engine to flood, but it wasn't explained why.[/QUOTE]

Coolant temp sensor for fuel injection is like a choke. The colder the engine is the longer the injector stays open. If the engine is 160 degrees and the sensor thinks its 50 degrees, then you got hard starts or no starts possible.

[StickMon]

Originally Posted by rkstar9

... how will I know when the fuel is dissipated? ...

If it goes anything like the throttle-body injected Chevy's I've started, as soon as one or more plugs fire it'll ignite the fumes in the intake and sneeze.
Then it'll start firing more and more and eventually start, just on the fumes, and then run out of gas.
Then you reconnect the fuel and it should start without too much problem.

[rkstar9]

It started with a jump from my e150
Battery appears to be fine as well, only left it sitting overnight yesterday but it seems fine.

Thanks everyone.

Update:

the car failed to start one more time and even the dome light strugled to turn on.

So I left the car sitting for about 2 weeks in the cold. One slightly warmer day decided to go jump start the car again with the e150. But just for shits and giggles tried starting it as it was without the jump. It started right up! even after the battery was completely dead and sat for 2 weeks!

then immediately I took the car to autozone and battery tested just fine.

I guess the morale of the story is these batteries are not made for -30f weather.
and even after your battery is dead because of the cold, it can come back on it's on once temperature is restored.

[ZStig]

I'd be afraid of damaging something by cranking the car for so long. I only try to start it for about 4-5 seconds at a time.

I'm having a fast crank but no start issue fairly often, so I'm replacing the crank position sensor tomorrow as per my research