Cold Start Issues

[R0ME0]

Hi Guys,

My 08 Z4M coupe seems to be having starting issues usually after its been sitting for 8+ hours. Usually from leaving the office of heading to work in the AM. When I put in the key it and turn it to start it seems to take a few seconds for the car to start up and turn over when it starts up it seems to idle a bit rough and drop in RPMs and then stabilize after a few seconds (will try to get a video). My hunch is that the spark plugs / starter is going bad. Car is still under warranty but I wanted to get others feedback on what the issue may be or if you've experienced this yourself. Thanks in advanced!

[elwesso]

If the battery is original that could be something to look at... If it seems to crank slower I'd check the battery first.. If the battery was made in 2008, that means it's 5 years old, and on borrowed time IMO.

[Shorts]

If it turns over strongly but takes a while to start it might be your MAF sensor

[mgwatson48]

Is it like my car?

http://www.zpost.com/forums/showthre...ighlight=vanos

[R0ME0]

Originally Posted by mgwatson48

Is it like my car?

http://www.zpost.com/forums/showthre...ighlight=vanos

I have a service appt sat for them to address it under the 2 month 2000 mile warranty. And to answer your question no. My idle definitely isn't that bad but it does jump a bit on a cold start. i will get a video tomorrow in the AM. Thanks for everyone's feedback so far.

[intoflatlines]

I just posted a thread about this same issue, but mine doesn't have to sit for a long time for it to happen.

http://www.zpost.com/forums/showthread.php?t=826174

[R0ME0]

Originally Posted by intoflatlines

I just posted a thread about this same issue, but mine doesn't have to sit for a long time for it to happen.

http://www.zpost.com/forums/showthread.php?t=826174

Thanks for the post mine sounds exactly the same as you have in your video. Going into service on Sat so hoping for the best.

[intoflatlines]

Let me know what the results are...

[StickMon]

Mine does exactly the same thing on "cold" mornings.
A "cold" morning here is 45-50°F.
Has to turn over a few times to start, surges as expected, almost dies, then picks back up to normal fast idle.
I know my exhaust camshaft is out 14° after a semi-botched vanos bolt replacement by an indie mechanic.
The vanos sets it's position to be "advantageous for starting" when you shut the car off. I was thinking that the exhaust camshaft isn't where it was expecting it to be, and it took it a few seconds to sort out, but so many others are reporting it, now I'm not so sure.
I'll be resetting the camshaft within the month. We'll see if that does it, if we have any more "cold" mornings that is.

[R0ME0]

Originally Posted by intoflatlines

Let me know what the results are...

Just heard back looks like it was a fuel pump issue with the car not getting the correct fuel pressure. Hopefully this is actually the issue. Keep you posted!

[MakoBimmer1]

R0ME0...I thought it was the cold weather affecting it and never thought anything of it because after it warms up, it drives spectacular. I did have the battery replaced a few months before trading it in though. You have a new battery already now.
--Chad

[R0ME0]

Originally Posted by MakoBimmer1

R0ME0...I thought it was the cold weather affecting it and never thought anything of it because after it warms up, it drives spectacular. I did have the battery replaced a few months before trading it in though. You have a new battery already now.
--Chad

Good to know thanks Chad! Got the car back but seems like the cold start issues have gotten worst. I will post a video later. So far they have replaced the MAF and fuel pump. Looks like the car is going back to the dealership to see what else it can be...

[TexasCutter]

Originally Posted by R0ME0

Good to know thanks Chad! Got the car back but seems like the cold start issues have gotten worst. I will post a video later. So far they have replaced the MAF and fuel pump. Looks like the car is going back to the dealership to see what else it can be...

Was this ever figured out? Mine cold starts pretty rough also...and usually has quite a few cranks before it turns over. However, within <5 seconds, the car is fine and idling perfect.

Also.. if it get it up to a decent running temperature and turn it on and off, the car doesn't experience the same problem. Is yours like that?

[R0ME0]

So looks like the issue has finally been fixed (its been 3 days since I got her back). They replaced the following: MAF Sensor, Fuel Pump, and T-Shape Idle Regulating Valve. So far so good. Took them a long while to figure it out. But the dealer acted very clueless when troubleshooting. Just glad that I finally have her back in my possession. Hope this helps you guys out there.

[Pheonix]

Originally Posted by R0ME0

Good to know thanks Chad! Got the car back but seems like the cold start issues have gotten worst. I will post a video later. So far they have replaced the MAF and fuel pump. Looks like the car is going back to the dealership to see what else it can be...

Great, Thank you for posting the result Does it mean they replaced the MAF and Fuel Pump for no reason?