+ Reply to Thread
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 14
  1. #1
    VXRed Foli's Avatar
    Join Date
    20th April 2017
    Posts
    26

    Default Losing boost with induction kit

    Good morning,

    Yesterday I fitted an induction kit to my VXR which I've owned for 3 days, it's the direct to turbo feed kit using Roose silicone pipes and a cone filter. The filter seems a little on the small side to me but to be fair it does fill most of the available space and I collected it from the previous owner who had it fitted previously.

    The issue is under heavy boost always around the 4500rpm area it now seems to choke the engine as if it isn't getting enough air through and I lose boost and it pulls more like a 2.0 N/A than a 2.0T. I should mention that prior to fitting the kit there was no issue whatsoever and it pulled right to the redline like a lunatic.

    My question is could it be that the filter itself is too small and so restricting the air flow under heavy load or could it be the standard pipes on the right side of the engine bay sucking themselves flat and choking it off?

    It could be anything else as well I guess but these are all I can think of right now.

    Other info:
    3" stainless cat back & remap


    Thanks in advance.


    Sent from my iPhone using Tapatalk Pro
    Last edited by Foli; 21st April 2017 at 09:13 AM.

    Crossover delete, ITG cone filter
    3" cat back by Fast Road Conversions

  2. #2
    VXR enough andrewt1971's Avatar
    Join Date
    25th January 2010
    Posts
    3,135

    Default

    I've had similar problems way back on different occasions for different reasons. One the direct route was messing up the maf readings causing throttle closure, the boost would drop to around 8psi ish. That needed a map tweak to fix. The other time the boost would drop to zero and the engine would have a very gentle smooth missfire but still accelerate, that turned out to be spark plugs, even though swapping back to the stock air box cured the misfire and it generated no error codes!
    I'd be very wary of running a stage 2 map on the stock cat.

  3. #3
    VXRed Foli's Avatar
    Join Date
    20th April 2017
    Posts
    26

    Default

    What little info I have from the previous owner the plugs have been changed in the past 6 months and it was mapped with the exhaust and filter fitted.

    Is it worth me trying new plugs regardless and seeing if it fixes the issue or am I better off just putting the standard air box back on and forgetting about it until I can get to someone to look at it?

    I'm going to order up a downpipe and potentially a sports cat next week, looking into prices and researching different brands at the moment.


    Sent from my iPhone using Tapatalk Pro

    Crossover delete, ITG cone filter
    3" cat back by Fast Road Conversions

  4. #4
    VXR enough X8 DUD's Avatar
    Join Date
    26th October 2012
    Posts
    2,593

    Default

    Sounds like a MAF calibration issue, have you checked to make sure the MAF is pointing in the right direction and has sufficient length on the extension cable?

    Haven't seen or used Roose hoses, but check to make sure the hose isnt collapsing when higher in rev range
    Arden Astra VXR Cobra turbo back non-res, Direct route intake, Mfact Plated Diff, Airtec fmic, RARB, DAP's, Enhance Gearbox Breather, RND Droplinks, Heko's, Courts Braided Lines, DS2500 pads, Superblue fluid, led plate bulbs, side lights, fogs, Blue interior led's Forge recirc + actuator, stage 3 map Cams + more to come Build Thread: http://www.vxronline.co.uk/forum/sho...6-X8-DUD-Arden

  5. #5
    VXRed Foli's Avatar
    Join Date
    20th April 2017
    Posts
    26

    Default Losing boost with induction kit

    I was very careful to make sure it went back the right way round I did check it a few times.
    The cable is good and the hoses are rock solid so there's no way they're collapsing.


    Sent from my iPhone using Tapatalk Pro

    Crossover delete, ITG cone filter
    3" cat back by Fast Road Conversions

  6. #6
    VXR Nothing comes close VXRRy's Avatar
    Join Date
    15th May 2013
    Posts
    15,845

    Default

    I'd be double checking that the MAF is facing the correct way and that the arrow is facing forwards the turbo. It's a simple mistake to make.


    Sent from my iPhone using Tapatalk

  7. #7
    VXRed Foli's Avatar
    Join Date
    20th April 2017
    Posts
    26

    Default

    Just double checked and it's 100% pointing toward the turbo. You can't see from the photo as it's marked on the bottom but it is marked the right way, I checked.


    Sent from my iPhone using Tapatalk Pro

    Crossover delete, ITG cone filter
    3" cat back by Fast Road Conversions

  8. #8
    VXR Nothing comes close VXRRy's Avatar
    Join Date
    15th May 2013
    Posts
    15,845

    Default Losing boost with induction kit

    Yeah, nowt looks wrong with that tbh. I wouldn't be concerned with the size of the filter either, seen smaller.

    Does the filter seem heavily oiled though?

    Quite possible that there is some MAF contamination if it is


    Sent from my iPhone using Tapatalk

  9. #9
    VXRed Foli's Avatar
    Join Date
    20th April 2017
    Posts
    26

    Default

    If anything it seems bone dry, certainly not over oiled.

    Also tried pedal test and nothing came up. Below 4500 it pulls like it should do then it just seems to smash into a wall and not do much above 4500 but an hour before fitting the cone kit it was pulling to the redline. Nothing else has changed other than adding the filter.


    Sent from my iPhone using Tapatalk Pro

    Crossover delete, ITG cone filter
    3" cat back by Fast Road Conversions

  10. #10
    VXR Nothing comes close VXRRy's Avatar
    Join Date
    15th May 2013
    Posts
    15,845

    Default

    Tried refitting the standard crossover?



    Sent from my iPhone using Tapatalk

+ Reply to Thread
Page 1 of 2 1 2 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts