Jump to content
The mkiv Supra Owners Club

AVCR Boost Problem


Guest Jason1

Recommended Posts

Guest Jason1

Hi

 

I have now fitted a AVCR to my car and just wanted to get it all setup for 1bar.

 

However I cannot control the boost, I just hit fuel cut no matter what the settings.

The head unit shows all the correct readings and I am convinced the hoses are correct.

 

If I lower the duty it is the same, so everything low still the same.

Turn the unit off and still the same..

 

Very confusing this,, would this be a solenoid problem?

I cannot here it ticking which my last unit did

 

Any help guys?

Link to comment
Share on other sites

Guest Jason1

Hi

Yes with it all plumbed in and on lowest setting Fuel Cut every,time cant tell what boost as just cuts the car but hits 1.2 pretty quick lol

 

Even with the unit set to off it is the same.

If I put the boost hoses back I get .9bar as this is what the car does anyway

I haven't tried connecting it up and the unplugging the solenoid, would this be ok to do?

 

Any help would be great as at the minute it is just a very expensive boost gauge

Link to comment
Share on other sites

Guest Jason1

I think so

 

I followed the instructions to the letter

The head unit gives all the correct readings and sensor checks

shows the rpm throttle and boost no problem so I am happy with that.

I also plumbed in according to the manual and capped off the vsv and lower wastegate ports

So I think it is all ok,

 

Would I cause damage with the solenoid disconnect?

Or would it just run spring pressure?

Link to comment
Share on other sites

I think so

 

I followed the instructions to the letter

The head unit gives all the correct readings and sensor checks

shows the rpm throttle and boost no problem so I am happy with that.

I also plumbed in according to the manual and capped off the vsv and lower wastegate ports

So I think it is all ok,

 

Would I cause damage with the solenoid disconnect?

Or would it just run spring pressure?

 

Take a picture of how you have the solenoid connected :)

Link to comment
Share on other sites

as scott suspects i believe you have the vac pipe on solinoid point , i think with the stock set up you need the n/c pipe,

 

but please be aware that the avcr will give you 20% more boost then you have as stock so you may still hit fuel cut , but with the avcr switched off you should see stock boost again but a little lower

Link to comment
Share on other sites

Guest Jason1

Sorted ish

 

I had the NC pipe fitted instead of the No or ON depending on which way you look at it.

Sort of setting it up now and I have a steady 1bar apart from 3rd gear which spikes hits FCD and then sits at 1bar

Duty cycle is set as low as it will go at 20 so I am hoping that it will go into self learn mode and sort itself out

in the next couple of days.

Thanks

Link to comment
Share on other sites

Guest Jason1

Hi thanks for the help.

 

However this is what I have discovered.

The car at 20% Duty would hold 1Bar except in third where I would hit fuel cut.

So I turned the unit to off and low and behold I discovered the car (according to the AVCR) held 1Bar anyway in all gears no problem

My car is BPU with a 1Bar restrictor ring and so I thought perhaps the unit when on would struggle keeping the car at what it already produces.

And so I left the unit off and concentrated and getting all the other settings right, Gears etc.

 

This is the confusing bit.

I have now changed all the hoses on the car for silicone ones, as the ones fitted to the car were tired(silicone also)

I have replaced like for like sizes etc, apart from the hoses to the AVCR solenoid, I did these with 5mm id hose.

The one for the AVCR boost sensor is 3mm id the same for the map sensor etc,

Since I have done this, I turned the unit to on and it boosted low .9bar

So I have put in target boost to 1Bar and had to raise the duty to 47% to get the car to boost to 1Bar.

Why would this be?

Would the 5mm hose tot he solenoid be wrong?

Although the car boosts up sooner and seems to run ok, and there is the shove at 4k it doesn't feel as tight as it was before

Any ides on this?

Link to comment
Share on other sites

Larger ID means a couple of things.

 

1... More chance of leaks, the increased ID means less of a seal on the mating port. If this happened, you would have a boost leak and need more WG control to keep pressure.

 

2... More volume to fill. The increased ID means more volume of air is required to fill the hose space. In this instance the increased time would allow the solenoid more time to react. Fractions of a second, but that's all that it would take really.

 

My money would be on reason 1, but reason 2 is feasible.

Link to comment
Share on other sites

Guest Jason1

I have sealed the hoses (zip tied)

 

I used the 5mm hose as the solenoid has large barbs and so the 3mm would be really tight to get on

The one for the boost sensor is smaller and so I used the 3mm and this is the same as the other hoses from

the intake.

Does anyone know the correct id hose size for the AVCR?

Link to comment
Share on other sites

Guest Jason1

That's true

 

Did yours pull strong or felt a little flat?

Don't get me wrong the car shifts, but just doesn't feel 100% compared to what it did

Oh I see of course if it was bleeding boost then it would feel different

Link to comment
Share on other sites

Guest Jason1

Sorted

 

I have dropped the id of the hose to the avcr solenoid to 4mm

Also changed the NE points back to were they were so not ignoring the 4000rpm mark

And hey presto it hits a rock steady 1 BAR in all gears and it has now gone into self learn mode

Pulls like a train and I am happy with it

Hopefully it will now sort itself out.

I agree though I need a FCD already have a pump fitted 255lph one so should be ok.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue. You might also be interested in our Guidelines, Privacy Policy and Terms of Use.