Car doesnt like to start on the first try

[NWFZHP2005]

So when I get in the car and turn the key it turns over no problem. If it sits for even 10 min I have to apply throttle and it runs perfect. Any ideas? It has catalytic converter codes but nothing else. I’m a mechanic but don’t have access to scan bmw currently.

[ZHPizza]

So when I get in the car and turn the key it turns over no problem. If it sits for even 10 min I have to apply throttle and it runs perfect. Any ideas? It has catalytic converter codes but nothing else. I’m a mechanic but don’t have access to scan bmw currently.Are you saying that, after sitting for some amount of time (10 mins+) but less than like, overnight, that it stumbles on startup until you give it throttle?

[NWFZHP2005]

Exactly. To the point without my intervention it could take 2-3 cranks to start. I’ve turned the key on and let the pump go for 20 or so seconds to see if it was building pressure and it made little difference.

[ZHPizza]

Exactly. To the point without my intervention it could take 2-3 cranks to start. I’ve turned the key on and let the pump go for 20 or so seconds to see if it was building pressure and it made little difference.But it starts up just fine if it sits for 8+ hours?

I had the same problem due to a leaking injector. Was getting rich condition codes too, which is what will kill the cats. I would shut the car off and the remaining pressure in the fuel rail would cause this one injector to slowly leak out fuel to the point that it would struggle to start without opening the throttle. If it sat long enough for the extra fuel to evaporate, though, then it would start up just fine.

I'll try to find the thread on it.

Edit: found it

http://www.zhpmafia.com/forums/showthread.php?t=6857

[NWFZHP2005]

I agree with the losing pressure for sure. I suspected that immediately however it makes no difference how long it sits but it starts a lot easier when full.

[NWFZHP2005]

Let’s say hypothetically I replaced the injectors due to a faulty one. Are there good aftermarket ones you would recommend?

[ZHPizza]

Let’s say hypothetically I replaced the injectors due to a faulty one. Are there good aftermarket ones you would recommend?Nah rebuilt/tested OE is fine. I think I paid $100 for a set on eBay

[NWFZHP2005]

Ok thanks. Ill see if the oil smells like gas.

[NWFZHP2005]

I don’t smell an unusually high amount of fuel in the oil. Nothing that concerns me. Now I have the issue where the fuel gauge only reads less than half when it’s full. I’m wondering if the fuel pump may be a concern. Allowing the fuel to drain back from the rail. Also might not have the volume at start up. I’ll check some stuff out and post what I find.


Also is is best to just get a BMW pump and sending unit or is there a quality aftermarket