Need input/Help - VANOS

I just got my car back from the mechanic and they are tellling me that my issues with a bad Idle when its cold are due to the VANOS in my 99' 528i going bad and its $1200 to replace it.

Now. They "unplugged" the VANOS they told me, so it wont cause any damage to the motor as it goes bad. What exactly am i losing or will this effect my car in anyway by having this unplugged? Also i know that it controls the timing on the CAM's i belive, by having this unplugged and driving it around will my car be damaged? Is this something that i NEED to have replaced within the next few months? or can it wait till spring?

-Branden

Reply to
Branden Nelsen
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No, it won't damage anything.

You are right, VANOS is a cam timing mechanism. It alters the valve timing to produce more torque at low speeds. Without it, all you will notice is flatter engine response.

On a 3 Series, this might not even be noticed by most drivers, but the added weight in your 5 Series may make the flat response noticable, and I assume undesirable.

The VANOS unit isn't very complicated, but the Cam Assembly is with some significant chains attached, and a special tool to hold the cams in place while the VANOS (and chains) are replaced. (I think you would be wise to replace the timing chains if you are going to replace the VANOS unit.) The unit isn't all that expensive, but the labor will run to about 6 hours, I think.

If you feel no driveability issues without the VANOS, I see no reason you can't drive without it. The only problem you should notice is in low-end performance -- starting off from stop signs and lights, that sort of thing. Once you get to freeway speeds, VANOS is done anyway, and you'll never know it isn't working.

Reply to
Jeff Strickland

Sounds like BS to me.

Reply to
adder1969

Dunno. I've not experienced it, but VANOS stuck in the 'advanced' position could well give a poor idle.

Reply to
Dave Plowman (News)

Does this describe the problem?

"It occurs on cold weather cold engine starts and takes the form of repeated engine attempted stalls and possibly a complete engine stall. The engine rpms drop dramatically and then recover. This then repeats after a few seconds of steady idle. The problem can be more definitively diagnosed by disconnecting the vanos intake or exhaust solenoid electrical connector. If the engine stalls cease then the problem is due to the vanos."

If so, then yes, you'll have to replace the entire VANOS because a couple of rubber seals have worn out:

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That said, driving with the VANOS solenoid disconnected won't hurt the engine, only performance.

Lemuel Johnson

Reply to
Lemuel Johnson

Thanks for all the replies.

Lemuel - That is the EXACT issue im having :)

So far my car is performing the same as when i bought it a year ago, so im guessing that it was dieing/dead from alonf time ago i just never noticed. So when i get it fixed id imagine im going to be suprised at the performance increase! :)

-Branden

Reply to
Branden Nelsen

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