XSeries-forum

Hello,

I'm reaching out to you today because I'm having an issue with my X5 4.4. I've been trying to pinpoint this problem for a few months now.

First, my X5 is a 2004 model equipped with the 4.4 N62 engine producing 320hp. When I start the vehicle cold and it begins its warm-up program (open/closed circuit) which lasts about 1m30, there's an issue when the engine transitions from open to closed circuit. The idle fluctuates between 900 and 700 RPM for 5-10 seconds before stabilizing at 600 RPM, the normal idle speed.

Here's the video for better understanding: https://www.youtube.com/watch?v=f_-dVTGKR3I. The phenomenon occurs starting at 1m43.

I've already changed the air flow meter, performed an intake leak test, cleaned the 4 VANOS solenoids (they were quite dirty), and cleaned the throttle body. I don't know if it could be coming from the engine or the Valvetronic system itself, but the motors work because I can change the Valvetronic opening value in INPA, and it affects the idle. I also think it might be the lambda sensors, even though I don't have any error codes. However, I did change one a few months ago because it was dead.

I'm out of ideas.

Thanks in advance!

Was all okay prior to changing Lambda sensor?....did you use an oem or aftermarket?

No it was the same before, i change it because i have an error code from INPA.

I bought a Bosch one.

You say youve changed the MAF was that a Bosch too?, also never a good idea to run that low on fuel...minimum 1/4 of tank....

Yes the new MAF is a Bosh.

when was the fuel filter last changed?

No idea

Always a good place to start.....you may even be pulling in air with the fuel that low.

I've had this problem for a long time, ever since I got the car (4 months).

Whats the mileage?, cant make it out on the video....there's a great possibility its you injectors coming to the end of life if your mileage is above 160kmh

It has 200 000 kms / 124 000 miles.
How can I check my injector ?
When the car reach his normal idle, the car run great.
Or maybe he doesn't have all his HP and I've never felt all the HP.

How did you do the intake leak test. Was it a smoke test? Got any oil leaks on the valve covers. Is the crankcase vent all in good nick.

Yes, it was a smoke test.
No oil leak.
When I repaired all the intake leaks, the smoke was coming out of the crankcase vent.
What’s is the goal of the crankcase vent? Is it supposed to release pressure inside the valve cover like a dump valve?

Crankcase vent should never have much pressure and it releases any gases/oil fumes etc into the EGR side for burning rather than to atmosphere.

Hello Everyone, I have Exactly the same car (2006 N62) and the same symptoms. however, I believe I have a valve gasket cover leakage (I get oil sip thru after long brisk drives) and I assumed it may be the cause. So I plan to replace the valve cover gasket sometime soon. not sure when