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Discussion Starter · #1 · (Edited)
Can anyone help.
When I come on boost its like its hesistating and not holding. A bit like it being on and off etc throughout the rev range. The car isnt misfiring as far as I am aware as it drives perfect when not on boost.
Its now only boosting between 0.6 and 0.85 where before it used to hit upto 1.0.I have checked the settings on the Apexi and even turned it on Mode Off to see if the problem lies with the settings on A or B but its still not boosting right. Seems to be worst when in 5th and boosting under load and not as bad when in 2nd etc.
Any ideas on what this can be?AFMs, leakage, Apexi AVCR unit or solenoid?

Brief spec Stage 1, Mines ECU, Apexi AVCR, Apexi filters, Mines downpipes, Biltz Nur Spec exhaust and decat, Trust Intercooler & ARC Oil Cooler.

Help would be most appreciated.Thanks.
 

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How old is the boost controller,could be faulty??! Mine went wrong after 3 months of owning,started over boosting!
 

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First thing i would do, check all the pipework for the Apexi boost solenoid, make sure everthing is jubilee/ziptied, check any pipework to aftermarket boost gauges, then i would check the intercooler pipework. Had mine come loose before and its just done it again, mine has gone from holding 1.7bar to only holding 1.3bar.

These are what i would do first as they don't cost anything, THEN look at the coilpack and plugs.

Hope you get the problem sorted mate.
 

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Discussion Starter · #7 ·
Thanks for the responses guys. Today i will check the plugs, coilpacks and the pipe work. I dont know how old the boost controller is.Is it worth reseting it if everything else seems ok?
 

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Discussion Starter · #8 ·
I checked the plugs and coil packs today.Plugs seem in good condition but old and the packs are in good condition with no signs of cracks.Not had a chance to test it yet but I will be heading out tonight.
As far as I can see there are no lose jubilee clips or splits in the hoses.
I may change the plugs anyway. What are the recommendations for my setup?
 

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Discussion Starter · #9 · (Edited)
I took the plugs and coilpacks out again today for another inspection.





As you can see plug 4 seems to be darker than the rest. Possible coilpack problem? I have wrapped the rubbers of the coilpacks with insulating tape to see if will improve matters. The base of rubber boot 4 also has some white deposit. Arcing? Also I noticed that the plugs are NGK PFR7A (11)? Is this the wrong grade of plug?Looks like a grade 7 with 1.1 gap. I will be changin them to BKR8EIX anyway.
The car is missing under load now.Gradually got worst.
Thanks
 
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