GA4 Setup & Remediation

Service · Analytics

GA4 setup and remediation

Analytics that reports the wrong thing is worse than no analytics at all, because decisions get made from it.

What goes wrong in GA4

The faults that survive for years without anyone noticing

Cross-site contamination

One shared Google tag firing across two or more websites, so one site’s traffic lands in another site’s property. On a recent account, 88% of the traffic recorded against one property came from a different domain.

Every report built on that data was wrong, and had been for over a year.

Quiet misconfiguration

Data retention left at the two-month default. Internal traffic filters created but never activated, so your own visits inflate the numbers. Duplicate tags counting every session twice.

None of these throw an error. The dashboard looks perfectly normal.

What I do

Diagnose first, then rebuild

01

Hit inspection

How many GA4 hits actually fire per page load, which measurement IDs are present, and whether a hardcoded tag is running alongside Tag Manager.

02

Contamination check

A hostname breakdown of incoming traffic to establish whether the property is receiving data from domains that are not yours.

03

Splitting merged tags

Separating a shared Google tag into its own destinations, with a hostname lookup so each site reports only its own traffic.

04

Property configuration

Data retention set to 14 months, internal traffic filters created and made active, unwanted referrals excluded, key events marked.

05

Orphan properties

Identifying legacy properties still collecting data that nobody looks at, and retiring them cleanly.

06

Ads linking

GA4 linked to Google Ads with auto-tagging on, and conversions imported so bidding uses the corrected data.

Worth knowing

Most of this is invisible from the dashboard

None of these faults produce a warning. The reports render, the numbers look plausible, and the only way to find the problem is to inspect what the site is actually sending.

That is the whole job. Check the measurement before trusting anything built on top of it.

Get in touch

Start with an audit. You’ll know what your account is actually doing.

Written findings, and a quote for the remediation. No obligation to take the quote.