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WydRyd WydRyd is offline
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Join Date: Mar 2002
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Backfire is usually caused by excess fuel dumped into the hot exhaust system passed the turbocharger (typically on DECEL), or it could have been a lean back-fire. If the latter, be very careful and ensure your A/F's are in check. You may have an air leak around the intake somewhere (perhaps an intake manifold gasket got sucked in, creating a vacuum leak)?

Torque down your intake manifold nuts as un-metered air will cause the motor to run lean, and you certainly don't want this on a turbo motor

Has it done it again since? Whilst the motor is running, spray carb cleaner around where the intake runners meets the heads and see if it makes a difference to idle quality. if so, then you have popped an intake manifold gasket. This commonly happens on 3.2 Carrera's too... ask me how I know
'89 911 Turbo Cab
Protomotive MAP ECU, Twin Plugged Heads, GT2-EVO CAMs, 3.3L fully finned P&C's, ARP fasteners, C2T head gaskets, Titanium Retainers, Turbo spec valves, springs & guides, 964 splash valves, GT35R BB turbo, GSF Stainless Headers, Magnaflow Exhaust, Full bay Intercooler, TiAL 46mm w/gate, TiAL 50mm BOV, Apexi AVC-R EBC, SPEC Stage3+ Clutch kit, Crane CDI Ignition

Last edited by WydRyd; 05-09-2007 at 09:49 PM..
Old 05-09-2007, 06:03 PM
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