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Boost Spike

Maddog309

By Maddog309,
in Engines & Forced Induction

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Maddog309 Apprentice

Maddog309

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Hey guys, got my car back from the mechanic yesterday, after a full engine rebuild. I've since noticed that it has been boost spiking like a whore and im not liking it at all. It is set to 12 psi on the boost controller, just to run the engine in, didn't want to set it to its usual psi level. I am seeing spikes over 20 psi. Is my boost controller f**ked or maybe my external waste gate?

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Maddog309 Apprentice

Maddog309

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Found the problem... inspected and hose from boost controller to wastegate was split, got a new one and fixed it up and she runs sweet now! The only problem is, my stupid self didnt think to look for 2 days now, the car was boosted a couple times before I realised that it feels like wayyyy too much for 15 psi. Could those couple of likely of caused an internal damage? the car seams to be running smooth as, just a little paranoid.. have further turned it down to 10 psi and keeping it low until I get the power tune done after a couple thousand k's

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Maddog309 Apprentice

Maddog309

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Hahaha oh man.. that is crazy! Yeah car seems to be idling all good, runs well on 10psi now. Im just paranoid from when it was in the mechanic last, just really hope it didn't do any damage internal wise. Was only a couple and was hardly boosted, but when it was it was hitting very high psi until I noticed :(

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https://www.sau.com.au/forums/topic/438818-boost-spike/#findComment-7193820
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Maddog309 Apprentice

Maddog309

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Yeah I know I cant change it haha. But since that's happened should I run a compression test or something just to make sure the internals etc are all good? or is that not needed. Car runs fine, idle is good. get a bit of backfire every now and then but I think that's just because I need a tune.

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Josh080691 Rising Star

Josh080691

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Nah comp test isn't require unless something seems wrong. I'm sure it's fine I had this problem when I overboosted three times due to new boost controller setup wrong but all sweet two years later I did comp test at 172-168 across all cyl's

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