There is a MSF Thread somewhere covering this. From memory it was to do with a high pressure fuel spike on cold start for cars (mostly but not always) with STAGE2+ maps.
The reason being that the issue normally occured between 1750 - 1770PSI and the stock maps only require ~1700PSI maximum. In the numerous logs done there was nothing to suggest a dip / drop in pressure.
There are a few fuel trim adjustments that can be made to fix it but there was no evidence found to say it would be a long-term issue.
From experience it never caused any issues:
Autotech HPFP #1 - Never squeak / squeal. Several thousand KM's later it failed.
Autotech HPFP #2 - Squeaked every so often on cold start. Never had any issues.
Last edited by DAN MPS 3; 03-03-2014 at 12:26 PM.
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