HkS EVC III

PobodY

Moderators
Staff member
I'm pretty sure that this has been covered before, but I can't find it at the moment.

Basically my EVC III has been fine for quite some time, but lately it has taken to boost spiking (i.e. it's set at 0.9bar, but as I pull onto the highway and put my foot down the gauge goes past 1bar... and the over-boost alarm starts chiming). So the controller sees that it's overboosting, but doesn't actually do anything to stop it (I just back-off or change gear rather than let it keep going).

I know that a few people have seen this problem, and that they sometimes don't let you set the boost as high as you want it. - So, has anyone worked-out what the problem with them is and how I can fix it?

I'd guess it's the valve its self; possibly the stepper is sticking and not letting boost get to the actuator and open the wastegate. - Anyone know how easy it is to service that? Can I get new O-rings for it for anywhere?
EDIT: Looking through some of those old threads, people seem to suggest that it might need a good clean-out because I've never replaced those filters. Is that still a recommendation?

I don't do anything special; it operates in 'manual' mode in a state of 'on' at 0.9 bar or 'off' which is just the actuator on the turbo (for when my wife is driving).
 
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paz

Active Member
The only time I had this problem (different device tho) the spring had snapped in the bov causing spiking.
 

PobodY

Moderators
Staff member
I'm pretty sure that the SQV is still working.

I've sent an email to HKS Europe to see if it's a known problem (with a known solution). - I have seen a couple of sites that say "check your offset" and say that it may not be overboosting by that much; just that the boost is building quicker than the unit expects so it overshoots before it opens the wastegate.
 

PobodY

Moderators
Staff member
Well, HKS have got back to me. They say:

unfortunately we cannot offer much advice or help with the EVC III as the product was discontinued before HKS Europe even existed (some 15+ years ago now) and we have no previous experience with the units as they are so old. HKS Europe also only offers support for the products we ourselves have supplied through our own authorised European dealer network. We do not offer support for second hand products or products purchased from non authorised European sources.

I can however tell you that all EVC for the last 10 years have been supplied with a stepper motor and not a solenoid. It is only last year that we re-introduced a new entry level boost controller with a solenoid control valve.
The current and previous stepper motors and the new type solenoids are not serviceable in anyway and we do not offer a repair service for these items as it is not economical to repair them. Once they are worn out they must be replaced with a complete new EVC unit which is actually more economical than repairing them.

The longevity of a stepper motor (or solenoid) can greatly be reduced if the inline vacuum filters are not replaced on a regular basis. The filters are there to stop contaminants entering the stepper motor. If the stepper motor becomes contaminated by dirt particles this will lead to excessive wear on the mechanism and it will not be able to hold stable boost levels.

This could be the cause of your problems or it could just be that the unit is very old and just worn out. Unfortunately they do not last forever.

So maybe it's just that my unit is dead. - I'll try giving it a clean, but it sounds like it might be a lost cause.
 

stumo

Active Member
Just get one of these....



two stages of boost (three if you turn it off, it then relys on the actuator), dead easy to setup (you just dial-in your PSI, no messing with gain, percentages etc etc) and only 400 dollars.
 

PobodY

Moderators
Staff member
That's about $350 more than I've got to play with at the moment.
Still, you're quite right; that's all I need.

Maybe I'll keep my eyes peeled.
 

PobodY

Moderators
Staff member
I've got a bleed valve already. I can put it back in... I just like being able to turn the boost down when I hand my wife the keys; she's already got 6 points from going past cameras at 10mph over the speed limit. :doh:

What's odd is that it doesn't overboost if you come off the lights hard, but it does if you're holding 3rd on a bend then nail it.
It's not a problem to watch the boost gauge and back off when it gets to 1bar, but it doesn't seem like a smart idea to put it on a rolling road when I can't stop it boosting.
 

gtirjoey

Member
could be worth taking the case off the solenoid to give it a good clean out inside,
i would pesonally change the actuator hose as well just to rule it out.
 

PobodY

Moderators
Staff member
That's pretty much what I was thinking. - No harm in taking it apart and having a go at cleaning the motor. It can't be completely shot or it would never work.
 

PobodY

Moderators
Staff member
Well, it worked for the first trip... then it went mental and was telling me it was overboosting at 0.5bar.

I think it's time to put my bleed valve back in; pity because I quite liked the EVC and thought I'd fixed it.
 
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