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Does anybody know what would cause intake detonation. This is racking my brain. I have tried everything. Retarding the cam, adding fuel, taking away fuel. I know it is detonating through the intake cause it keeps pushing out my IAT sensor. It is fine at half throttle but as soon as I go to full throttle and the boost starts to get to 3psi POP. Please help. Also I have the TSI turbo kit if that helps. I run 91 octane with an octane booster also. Never had this problem until I got here in Cali. Man I miss germany. I was running 100 octane there and never had a problem.

 
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is your iat before the charge pipe or in the charge pipe?

 
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Silicone it in. And the sensor should ALWAYS be after the turbo and intercooler.

 
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afaik, octane boosters only raise octane by 1 point ... which means 91 octane + booster = 91.1 octane =\

you shouldn't be detonating in the first place ... being too lean causes it, not having enough octane (but even at 3 psi, you should be ok) ... being too rich causes backfiring ... which is what it sounds like if you can hear a loud popping sound

 
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its is firing back in to the intake. that is what is causing the iat to pop out.

 
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How can you tell?

 
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loud pop in the charge pipe and it is pushing out my IAT sensor.

 
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OMG man...you've GOT to be kidding. You don't detonate in your intake, it doesn't work like that. What's pushing your sensor out is BOOST - At full boost (i.e. full throttle), you have 7-14 psi above atmospheric pressure trying to push outwards. You need to clip that sensor in, weld it on, or JB Weld. But for god sakes, you're not "detonating in your intake"... Do some research on turbocharging...

BTW.. you can attribute this to California's atomosphere because more than likely, you're at sea level and air is much more dense and abundant than German atmosphere.

 
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Ok first of all you need to study up on combustion engines. If the fuel is unstable when it enters the intake chamber it will detonate due to the intence heat in the engine. when it does the intake valves are still open there by detonating in to the intake manifold and pushing out the IAT sensor. I have run the car at 14 psi and never pushed out the sensor. I can't even hit 3 psi and it detonates. And yes you can detonate in to the intake. if one of your valves are stuck open it will fire back in to the intake manifold. Take your own advise and research your self.

 
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you never fuc-ked with the valve timing right?

 
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^^^aka adjusting cam gear

 
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yes I took it retard 2 deg. and back to stock. still does it either way.

 
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Check the valve lash.

 
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I think technically it would be considered a backfire through your intake. Detonation by definition can only happen in the combustion chamber. Any moderate amount of positive pressure in the intake and the sensor will most definately pop out. Also if you put the cam gear on yourself check that it isnt advanced from putting the belt on wrong or the belt jumping time. If so it makes a really harsh sound in the intake. Sometimes it will backfire if its far enough advanced, valves may also have been bent. If you played with valve lash it may be set way too tight.

 
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Dude, your intake charge doesn't "detonate" unless EITHER one of two things occurs -

1) The charge is extremely compressed - the pressure increases the temperature drastically to the point where the oxygen molecules in the air charge are forced to react with the hydrocarbons in the fuel ---> combustion. (Temperature/pressure is NOT high enough in your intake manifold to cause such events. If it is, you have other problems)
2) A spark plug introduces a spark which heats up a large enough pocket of air/fuel charge to ignite, chain react, and combust the rest of the chamber.

So... YOU tell me, since you're the expert here, how the intake charge just *detonates* in the intake manifold? If you have that little sensor just hanging in there, it WILL blow out when the manifold gets any amount of positive pressure. Positive pressure pushes outwards, trying to escape... Hence the easiest method of escape, a loose sensor, gets blown out to relieve the pressure. What the hell don't you understand?

Secure the sensor and check your valves - If one or both of the intake valves were loose, you could have either ignited intake charge spreading into the intake manifold, or you're forcing the charge out so quickly during the compression stroke that it's forcing the sensor out (not likely). YOU do your own research before you criticize someone else.