335D smoking issue

Oogle44 · 03-02-2020, 04:48 PM

Hello

I own a 2007 335D E92 which has been remapped.

For the last 6 months I have been completely chasing my tail with it trying to sort a couple of issue including an issue with it smoking on startup. See video:

This only happens on a cold start, and the smoke clears after about a minute. It also has a distinct smell of unburnt fuel to it. I've had the turbos checked, they're fine, I've had a new intercooler, new boost pipes, changed the crankcase breather. I'm wondering if my last port of call is maybe glow plugs? The car also feels like it's struggling to start a bit on a cold sometimes, but not all the time. As you can see from that video it start fine but is a bit lumpy when it does. I'm just wary of throwing more money at it because I've already spent a fortune. And it's a big enough job to get to glow plugs if that is the problem. So I want to be sure.

Any ideas or anyone had a similar issue?

Any help greatly appreciated.

Thanks

def1nity · 03-09-2020, 07:34 PM

That's a leaky injector I'm pretty sure. The reason why it smokes so much on cold start is probably condensation + an injector that leaks in the cylinder when the car is off. Then when you start, it smokes since the A/F mixture is messed up. That's why you can smell the unburnt fuel. The starting trouble is also a symptom of a bad injector, even in this video it is starting very wonky. It should start very snappy with quarter of a turn generally considered good. Go have them injectors diagnosed and you'll see. Driving like this can lead to catastrophic damage so sort it out asap if you want a car to drive/sell.

03-02-2020, 04:48 PM	#1
Oogle44 Registered 0 Rep 2 Posts Drives: BMW 335D E92 (Stage 1) Join Date: Aug 2019 Location: Northern Ireland iTrader: (0)	Hello I own a 2007 335D E92 which has been remapped. For the last 6 months I have been completely chasing my tail with it trying to sort a couple of issue including an issue with it smoking on startup. See video: This only happens on a cold start, and the smoke clears after about a minute. It also has a distinct smell of unburnt fuel to it. I've had the turbos checked, they're fine, I've had a new intercooler, new boost pipes, changed the crankcase breather. I'm wondering if my last port of call is maybe glow plugs? The car also feels like it's struggling to start a bit on a cold sometimes, but not all the time. As you can see from that video it start fine but is a bit lumpy when it does. I'm just wary of throwing more money at it because I've already spent a fortune. And it's a big enough job to get to glow plugs if that is the problem. So I want to be sure. Any ideas or anyone had a similar issue? Any help greatly appreciated. Thanks
	Appreciate 0 Tweet Quote

03-09-2020, 07:34 PM	#2
def1nity New Member 0 Rep 7 Posts Drives: e90 330d pre-LCI Join Date: Sep 2018 Location: Bulgaria iTrader: (0)	That's a leaky injector I'm pretty sure. The reason why it smokes so much on cold start is probably condensation + an injector that leaks in the cylinder when the car is off. Then when you start, it smokes since the A/F mixture is messed up. That's why you can smell the unburnt fuel. The starting trouble is also a symptom of a bad injector, even in this video it is starting very wonky. It should start very snappy with quarter of a turn generally considered good. Go have them injectors diagnosed and you'll see. Driving like this can lead to catastrophic damage so sort it out asap if you want a car to drive/sell.
	Appreciate 0 Quote