Low Event Match Quality for signals

Area: Conversions · Updated: 5 Nov 2026 · Auf Deutsch · All articles

Symptoms

  • In Meta Events Manager an own or built-in signal has an Event Match Quality below 6 of 10.
  • Backfilled signals show action source “System generated” and only an external id.

Cause

  • Backfilled signals and signals after a lead change have no request of their own: without IP address and browser the event goes out as system_generated. X3 does not store IP and browser on the visit, only for at most 7 days on signal and conversion rows.
  • Many visitors arrive without a Meta click and without _fbc/_fbp (those exist only after consent).
  • The Meta destination is set to “Click ID only”: then only fbc goes out, on purpose.

How to fix it

1. Check the Meta destination's matching data

  • In the dashboard: Einstellungen › Meldungen › Abgleich-Daten für Meta › Abgleich-Daten
  • With Claude (MCP): conversions_destinations_list {"project":"my-project"}

“Full” sends IP, browser, _fbp/_fbc, click ids, journey id and, for known leads, hashed e-mail, phone and names. “Click ID only” (Nur Klick-ID) sends fbc only.

2. Let a signal fire live instead of backfilling it

  • In the dashboard: Einstellungen › Signale an Werbeplattformen › Eigene Signale
  • With Claude (MCP): ad_custom_signals_list {"project":"my-project"}

3. See the match quality in X3

  • In the dashboard: Sync › Karte „Meta“ (Abgleich sehr gut · gut · unsicher · schwach)
  • With Claude (MCP): conversions_match_quality {"project":"my-project"}

Meta updates the Event Match Quality in Events Manager with up to 48 hours of delay. ad_signals_meta_stats reads back what the dataset counted.

How to tell it worked

  • New signals show action source “Website” with IP address, browser and fbc when available.
  • The Event Match Quality rises within about two days.

fbc exists without an _fbc cookie too: when the visit has an fbclid in the landing URL, X3 builds fbc as fb.1.<landing time in ms>.<fbclid>, the same for signals and conversions.