[urq] EFI + MAC-14 maxing ataround 5k RPM

James Bufkin jbufkin at austin.rr.com
Wed Oct 24 06:11:56 PDT 2007

It doesnt sound like fuel to me.  If the cutout occurs at 5K regardless 
of load, its ignition related, A fuel cutout would be a high boost high 
RPM load where the PW is higher.
You should be able to use the WB O2 and the fueling map to see if its a 
certain PW# that correlates to the cutout.  That is fairly simple with 
standalone EFI to diagnose a fueling problem.
That being said...

You are using Audi MAC Ignition..  What wires are you using with the 
stock coil and dizzy?    For the interim unhook both your Knock 
Sensors.   I suspect something is triggering ignition problems at 5000 
rpms.    An ignition problem related to electronics or sensors will come 
down like a hammer at a set RPM regardless of load.  An ignition problem 
related to bad spark under boost might be intermittent and load 
dependent.   Unhook the knock sensors and gently give it a spin and see 
if it passes 5k.


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