DIY converted an Audi A4 170hp 2.0 tdi CAHA with cp3.
Bought the car with failed cp4 HPFP at 150k miles.
Fitted a used 1.4hdi cp3 pump
no# 0445010042 with stock metering valve no# 928400643.
Lathed the centre out of the 1.4hdi pulley and recessed it into the original cp4 pulley, then drilled and threaded the engine bracket to bolt the cp3 pump directly to the engine.
Made up an adapter for the hard fuel line and had to bend line a little.
Removed auxiliary pump, just unplugged wasn't enough it was restricting the fuel.
I would upload some photos if I could figure out how!
Going with the pump/meter valve info on here it was all straight forward and runs perfect, starts quickly and idles smooth.
Edit* should be link to photos here
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