How do you debug and troubleshoot GTM tracking issues?
We check in order, because a tag showing up in Preview isn't proof it reached GA4 or Google Ads. Each step rules out a different kind of fault. Network tab: are requests going to your own loader, or straight to Google? GTM Preview on the browser container: did the event fire, and which tags ran? Preview on the server container, if there is one: did the request arrive, and what went out? GA4 Realtime or DebugView, and the Google Ads conversion status. The next day's data, in BigQuery where we have it. The last step has caught things the others missed. Our technical tracking service includes the whole check.
Why Preview isn't enough
Preview tells you a tag fired in the browser. It can't tell you what the destination did with it. A tag can fire and still be blocked on the way, rejected for a missing field, or stored with a wrong value.
The order we work in
1. The network tab
We check that requests go to your own loader and not straight to Google's. If they don't, the setup isn't doing what it should.
2. Preview on the browser container
We confirm the page connected to the right container, the event appears, and the tags we expect ran. On our own setup, marketing tags wait for the visitor's choice in the cookie banner, and we check that too.
3. Preview on the server container
If you have a server container, it has its own Preview. We check the request arrives and the click ID going out is a real one.
4. The destination
GA4 Realtime or DebugView shows whether the event was counted. For Google Ads we look at the conversion status.
5. The next day
Some faults only show in stored data. If a Stape power-up called Click ID Restorer is set up wrong, it can write the word "stape" where Google's click ID belongs. We've found that on live sites. Preview looked fine, and the next day's BigQuery export showed it.
Our technical tracking service covers the whole check, and the Tag Manager page shows how we set containers up.
The tools in this answer
Where this came up in our work
Also worth asking
Other answers about the same tools.
What is technical and tracking infrastructure?
It's the set-up that counts what happens on your site and sends it where it needs to go: tracking tags, analytics, ad-platform conversions, your CRM connection and cookie consent, plus the hosting and security around your website.
How do you set up website analytics and tracking?
We agree with you what counts as a conversion, then set up Google Tag Manager and GA4, plus server-side tracking through Stape for sites that spend on ads. Before we hand over, we check the data is actually arriving.
How do you handle compliance management for my website?
We work with your cookie consent tool, or suggest one we've worked with, and connect it to your tags so they follow the visitor's choice. How that's wired depends on the project, so we test what your tags actually do. We don't write legal text or give legal advice, so your privacy policy needs sign-off from someone qualified.
What is ad platform integration and why does it matter?
Ad platform integration means joining your website, tracking and CRM to the ad platforms, so they receive the leads and sales that came from their ads. Without it, bidding learns from clicks and form fills instead of customers.
What is CRM and lead flow management?
A CRM is where your contacts and deals live. Lead flow is how an enquiry gets there: the form, the tracking behind it and the follow-up. We connect them so each lead arrives with its source attached.
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