The auto-stop/start on my '17 EB 3.5 has what I consider a somewhat dangerous problem and I'm wondering if there's a problem with mine or "they all act that way?"

The problem happens most often when I'm attempting to turn left across traffic in the middle of a busy road or intersection. I'll pull into the left turn lane and sit there with my foot on the brake (and auto-stop with the engine off). When it's time to giddy up across a gap in the traffic, the power steering is very slow to provide assist and I'm wrestling with the wheel to make the turn. After it happened to me unexpectedly the first time and I had to muscle up on the wheel to make my gap in traffic I started punching the button to disable auto-stop any time I'm in this situation. I tried an experiment today with it and from a stop with auto-stop enabled, from the time I take my foot on the brake and on the gas, it's a good 5 seconds or so before I have full power steering assist. That's just messed up. I'm surprised I haven't noticed this before now so I'm wondering if there's something wrong with my PS pump that it's not building pressure quick enough to work properly?

Any thoughts from the collective wisdom here?

 

No power steering pump in these
Its electronic steering now.
I don't have Start/Stop on mine though.

 

Interesting, did not know that. I wonder what explains the significant lag in getting my power steering back after an auto-start?

 

I do not have any lag when the engine starts back up. Power steering is available immediately.

I think a trip to the dealer is in order.

 

Mine does this..... shuts down the EPS (Electronic Power Steering) when its in Auto Stop mode.... In my opinion a safety issue as how you noted above.


My GLK350 does not shut down its EPS when in Auto stop mode.... Actually no other car I have ever experienced shuts down the EPS (I rent a lot of vehicles for business travel)


I just disable the auto stop every single time......there is no benefit to this feature IMO

 

Like he said no power steering pump, no fluid.

its EPAS - Electric Power Assisted Steering. V3 I believe now, maybe 4.

anywho - EPAS shuts off with engine stop to conserve system power draw - and yes all start stops turn it off on shut down.

It is supposed to be power back as soon as the engine starts - not 5 seconds later. I will have to check mine and see if it's noticeable. I've never noticed it before - I know it's got a touch of lag but never really had to fight the wheel.

If I happen to test it and time it I'll post that. But I've not noticed a lag before.

 

I wouldn't call it a safety issue since the EPAS is turned off only when the engine is stoped AND your foot is on the brake AND vehicle speed = 0.

(number of conditions in the computer for this to activate)

It is supposed to reactivate as soon as the engine is started - and being electrically driven it's near instantaneous power up. Make me wonder if either yours has a problem or maybe you've hit upon some unusual conditions that makes it activate late.

If there was a fault in the system you'd get a light on the dash
If the battery was low or weak the auto start won't activate

So it is curious.

 

My power steering feels like it's back on before the starter stops turning. I agree, you should demonstrate to the dealer.

Until you do that, use a little anticipation and just let off the brake enough to get 'er started a moment before you're going to take off.

 

My steering comes back instantly. No lag whatsoever. Time for a trip to the dealer.

 

My 2016 times it so that once the engine turns over, I can feel the assist of the EPS. I haven't ever paid attention to the time but with my normal time to take the foot off the brake to the gas, by the time by foot is on the gas the EPS is active or just turning on & that with me keeping constant pressure on the steering wheel to feel it. Either OP has a problem or OP is moving his foot off the gas extremely fast before the engine turns over