E39 out of breath

[Grand]

Dear all, My E39 year 99 seems to be running out of air when cruising. Say for instance, when I am cruising at a constant speed of about 110 - 120 kph, when i release the accelerator pedal while going down hill, the car seems to knock/choke a bit as if it is trying to catch some breath. I have just serviced the car and change the air filter, fuel filter, oil filter, engine oil, spark plug etc.Prior to this, when doing a diagnosis, the message which apear is "faulty solenoid valve". Any forumner faced this problem before?Cheers

 

[keray]

Probably a dumb question, you checked the solenoid valve ?

 

[Grand]

Have not checked the thingy. Asked the question to get some prior feedback before approaching the mechanic as he told me may have to open up the engine. Rather annoyed with the word "dumb question" though.

 

[leforte]

which solenoid is this? did the mech show you the computer diagnostic of the fauty part?

 

[absidian]

There are a few solenoid valves in the engine and autobox.

Your solenoid valve fault would most likely be the vanos solenoid valve - you mentioned the engine was "choking" and "out of breath", both of which point to timing/fuelling issues.

The VANOS solenoid valve controls the valve timing - when this goes wrong the engine will be out-of-sync and possibly (trying to) stall whilst moving, hence the "choking" and probably spluttering at transient. The "out of breath" symptom you described is caused by the engine not operating at maximum efficiency due to incorrect valve timing.

I hope this is helpful. Could possibly be mistaken here, but this would be the most likely cause based what info there is available.

 

[pussy]

Probably a dumb question, you checked the solenoid valve ?

Have not checked the thingy. Asked the question to get some prior feedback before approaching the mechanic as he told me may have to open up the engine. Rather annoyed with the word "dumb question" though.

Grand,

Keray is quite harmless, but he gets you really thinking.

btw, must be the ICV solenoid, ti should regulate the air, once your trottle flap is closed, hence if the tension motor spring is not strong enough, then replace it.
if not, then your car will not idle neither can hold it running.

cheers.

 

[Grand]

Thanks for your informative reply, Absidian and Pussy. Will relay those information to my mechanic and see what he suggest. From the list of almost 85 workshop, may want to try out Optimum Automotive as it is quite near my working place and read some good comments about them. Hope this solenoid valve thing wont cost me a bomb!

 

[pussy]

Optimum is good.. most of the workshops listed are the ones all forumers use.. any problems, the forumers can help..

 

[Grand]

Pussy, do you know how to go to Optimum? Or if anyone have the tel number of Optimum, maybe I can call them up for direction.

 

[keray]

Optimum has gone expensive recently and not sure if Jason is still doing most of the work or one of the other mechs. Directions depending where you are coming from let's say going towards the damansara toll, go up the BU ramp to make a U-turn and turn in the small road where the furniture shops are, go parallel to the highway on the small road and eventually you will hit the block of shophouses where Optimum is.

And by the way when I said stupid question, I meant me asking a stupid question.

 

[Grand]

Thanks for the direction, Keray. Cheers, no hard feelings. I passed by the area just now (evening). Saw Bavarian Auto on the left side of the road if you are heading towards the toll. Will try them out soon.