Meta Ads Troubleshooting & Debugging

Comprehensive diagnostic guide for resolving Meta Pixel, Conversions API, and campaign tracking issues.

Symptom Library

Pixel Issues

• Pixel not firing - No events appearing in Events Manager
• Duplicate pixels detected - Multiple pixel instances on same page
• Events missing - Some standard events not tracking
• Delayed event reporting - Events appearing hours after occurrence
• Wrong pixel firing - Incorrect pixel ID detected

Event Quality Issues

• Event Match Quality (EMQ) below 6.0 - Poor attribution quality
• Missing parameters - Events lacking required data
• Partial event matching - Low match rates in Advanced Matching
• Incorrect event values - Currency or value mismatches
• Custom event not tracking - Custom events failing to fire

Conversions API Issues

• 400 Bad Request errors - Malformed API requests
• 401 Unauthorized - Authentication failures
• 429 Rate limiting - Too many requests
• Event deduplication failures - Double-counting events
• Test events not appearing - Server events not visible in diagnostics

iOS 14+ Attribution Issues

• 7-day attribution window - Limited tracking window
• Aggregated events only - Individual event data unavailable
• Domain verification required - Events not tracking without verification
• 8-event limit - Cannot track more than 8 unique events
• Delayed conversion reporting - 3-day delay in aggregated data

Campaign Performance Issues

• Zero conversions reported - Ads running but no conversions
• Conversion value discrepancies - Mismatch between pixel and actual revenue
• Attribution window confusion - Different windows showing different data
• Cross-device attribution gaps - Mobile-to-desktop conversions missing
• Ad disapprovals - Policy violations blocking ads

Investigation Workflow

Level 1: Quick Diagnostics (5 minutes)

Step 1: Check Pixel Status

1. Open Meta Events Manager
2. Navigate to Data Sources > Pixels
3. Look for green "Active" status indicator
4. Check "Events Received" in last hour
5. Verify most recent event timestamp

Expected: Green active status, events within last 15 minutes

Step 2: Browser Extension Check

1. Install Meta Pixel Helper (Chrome)
2. Visit your website
3. Click extension icon
4. Verify:
   - Green checkmark (pixel active)
   - Correct pixel ID
   - PageView event firing
   - No error messages

Step 3: Real-Time Event Verification

1. Events Manager > Test Events
2. Copy your browser's test event code
3. Perform action on site
4. Verify event appears within seconds

Level 2: Deep Diagnostics (15-30 minutes)

Event Parameter Analysis

1. Check Event Details in Test Events

// Expected event structure
{
  "event_name": "Purchase",
  "event_time": 1234567890,
  "event_source_url": "https://example.com/checkout",
  "user_data": {
    "em": "hashed_email",
    "ph": "hashed_phone",
    "client_ip_address": "192.168.1.1",
    "client_user_agent": "Mozilla/5.0...",
    "fbc": "_fbc_cookie_value",
    "fbp": "_fbp_cookie_value"
  },
  "custom_data": {
    "value": 99.99,
    "currency": "USD",
    "content_ids": ["product-123"]
  }
}

2. Validate Browser Console

// Run in browser console
console.log('Pixel loaded:', typeof fbq !== 'undefined');
console.log('Pixel version:', window._fbq?.version);
console.log('Pixel queue:', window._fbq?.queue);

// Check for errors
window.addEventListener('error', (e) => {
  if (e.filename && e.filename.includes('fbevents')) {
    console.error('Pixel error:', e);
  }
});

3. Network Request Inspection

1. Open Chrome DevTools > Network tab
2. Filter: "facebook.com/tr"
3. Reload page
4. Check for successful requests (Status 200)
5. Examine request payload

Event Match Quality Analysis

Navigate to: Events Manager > Data Sources > Your Pixel > Event Match Quality

Improvement Checklist:

• Enable Automatic Advanced Matching
• Implement manual Advanced Matching (hashed email, phone)
• Add Conversions API (server-side events)
• Include fbp and fbc cookie parameters
• Send client_ip_address and client_user_agent

Level 3: Advanced Diagnostics (30-60 minutes)

Conversions API Validation

1. Test API Connection

curl -X POST \
  'https://graph.facebook.com/v18.0/PIXEL_ID/events?access_token=ACCESS_TOKEN' \
  -H 'Content-Type: application/json' \
  -d '{
    "data": [{
      "event_name": "Purchase",
      "event_time": '$(date +%s)',
      "action_source": "website",
      "event_source_url": "https://example.com",
      "user_data": {
        "em": "309a0a5c3e211326ae75ca18196d301a9bdbd1a882a4d2569511033da23f0abd",
        "ph": "254aa248acb47dd654ca3ea53f48c2c26d641d23d7e2e93a1ec56258df7674c4"
      },
      "custom_data": {
        "value": 99.99,
        "currency": "USD"
      }
    }],
    "test_event_code": "TEST12345"
  }'

2. Review API Response

// Success response
{
  "events_received": 1,
  "messages": [],
  "fbtrace_id": "A1B2C3D4E5F6"
}

// Error response
{
  "error": {
    "message": "Invalid OAuth access token",
    "type": "OAuthException",
    "code": 190,
    "fbtrace_id": "A1B2C3D4E5F6"
  }
}

Attribution Debugging

Check for attribution discrepancies:

// Compare pixel data with server data
const pixelConversions = getPixelConversions();
const serverConversions = getActualConversions();

const discrepancy = Math.abs(pixelConversions - serverConversions) / serverConversions;

if (discrepancy > 0.1) {
  console.warn('Attribution discrepancy detected:', {
    pixelConversions,
    serverConversions,
    difference: Math.abs(pixelConversions - serverConversions),
    percentageOff: (discrepancy * 100).toFixed(2) + '%'
  });
}

Common Issues & Solutions

Issue 1: Pixel Not Firing

Symptoms:

• Meta Pixel Helper shows no pixel
• No events in Events Manager
• Browser console shows no fbq function

Diagnostic Steps:

1. Verify Installation

// Check if pixel code is present
document.querySelector('script[src*="fbevents.js"]')
// Should return: <script> element

// Check if fbq is defined
typeof fbq
// Should return: "function"

2. Common Causes & Fixes:

Cause: Ad Blockers

Solution:
1. Test in incognito mode
2. Disable ad blockers
3. Implement Conversions API (unblockable)

Cause: Script Loading Error

// Check for loading errors
window.addEventListener('error', (e) => {
  if (e.filename?.includes('fbevents')) {
    console.error('Pixel failed to load:', e.message);
  }
}, true);

Solution:
1. Verify script source URL is correct
2. Check for Content Security Policy blocking
3. Ensure script loads in <head> section

Cause: Incorrect Placement

<!-- WRONG: Missing wp_head() call -->
<head>
  <title>My Site</title>
</head>

<!-- CORRECT: wp_head() present -->
<head>
  <title>My Site</title>
  <?php wp_head(); ?>
</head>

Cause: Conflicting Scripts

// Check for multiple pixel instances
console.log('Pixel instances:', window._fbq_instances);

Solution:
1. Remove duplicate pixel code
2. Use single pixel instance
3. Consider GTM for centralized management

Issue 2: Low Event Match Quality

Target EMQ Score: 6.0+ (8.0+ ideal)

Improvement Strategies:

1. Implement Advanced Matching

// Basic pixel (EMQ: ~3.0)
fbq('init', 'PIXEL_ID');
fbq('track', 'PageView');

// With Advanced Matching (EMQ: ~7.0)
fbq('init', 'PIXEL_ID', {
  em: '7d6fd7774f0d87624da6dcf16d0d3d104c3191c5b77614e0fd9a9e0b5c4aa' + '1c0',
  ph: '5f86b2ad5cc6d64a96a69c45f326fde52b8bac37ea6e24c48f831f7e72a8' + '4c57',
  fn: '9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f0' + '0a08',
  ln: '3f47a7f0e9e7f5f1c5e3f1f0f1f0f1f0f1f0f1f0f1f0f1f0f1f0f1f0f1f0'
});

2. Add Conversions API

// Server-side event (higher match quality)
$event = (new Event())
  ->setEventName('Purchase')
  ->setEventTime(time())
  ->setUserData((new UserData())
    ->setEmails([hash('sha256', $email)])
    ->setPhones([hash('sha256', $phone)])
    ->setClientIpAddress($_SERVER['REMOTE_ADDR'])
    ->setClientUserAgent($_SERVER['HTTP_USER_AGENT'])
    ->setFbc($_COOKIE['_fbc'] ?? null)
    ->setFbp($_COOKIE['_fbp'] ?? null)
  );

3. Include Cookie Parameters

// Get Facebook cookies for better matching
function getFacebookCookies() {
  const fbc = document.cookie.match(/(?:^|;)\s*_fbc=([^;]*)/)?.[1];
  const fbp = document.cookie.match(/(?:^|;)\s*_fbp=([^;]*)/)?.[1];
  return { fbc, fbp };
}

// Send with events
fbq('track', 'Purchase', {
  value: 99.99,
  currency: 'USD'
}, {
  fbc: getFacebookCookies().fbc,
  fbp: getFacebookCookies().fbp
});

Issue 3: Conversions API Errors

Error 400: Bad Request

{
  "error": {
    "message": "Invalid parameter",
    "type": "FacebookApiException",
    "code": 100
  }
}

Common Causes:

1. Invalid Event Time

// WRONG: Future timestamp
$event_time = time() + 3600;

// CORRECT: Current or past timestamp (within 7 days)
$event_time = time();

2. Missing Required Fields

// WRONG: Missing action_source
$event = (new Event())
  ->setEventName('Purchase')
  ->setEventTime(time());

// CORRECT: All required fields
$event = (new Event())
  ->setEventName('Purchase')
  ->setEventTime(time())
  ->setActionSource('website') // Required!
  ->setEventSourceUrl('https://example.com');

3. Invalid Currency Code

// WRONG: Numeric currency
'currency' => 840  // USD numeric code

// CORRECT: ISO 4217 alpha code
'currency' => 'USD'

Error 401: Unauthorized

Solution:
1. Regenerate access token in Events Manager
2. Verify token has correct permissions
3. Check token hasn't expired
4. Ensure pixel ID is correct

Error 429: Rate Limit Exceeded

Limits:
- Browser events: No practical limit
- CAPI: 100,000 events per hour per pixel

Solution:
1. Implement exponential backoff
2. Batch events (up to 1000 per request)
3. Distribute load across time

// Batch events example
$events = [];
foreach ($orders as $order) {
  $events[] = createPurchaseEvent($order);
}

// Send in batches of 1000
$batches = array_chunk($events, 1000);
foreach ($batches as $batch) {
  (new EventRequest(PIXEL_ID))
    ->setEvents($batch)
    ->execute();

  // Rate limiting: wait between batches
  usleep(100000); // 0.1 second
}

Issue 4: iOS 14+ Attribution Problems

Symptoms:

• Sudden drop in iOS conversions (April 2021+)
• 7-day attribution window enforced
• Aggregated events only
• 3-day reporting delay

Required Solutions:

1. Verify Your Domain

1. Business Settings > Brand Safety > Domains
2. Add your domain
3. Add Meta verification meta tag or DNS record
4. Verify ownership

<!-- Add to <head> -->
<meta name="facebook-domain-verification" content="your-verification-code" />

2. Configure Aggregated Event Measurement

1. Events Manager > Aggregated Event Measurement
2. Select verified domain
3. Configure up to 8 events (in priority order)
4. Assign value to each event

Priority Example:

1. Purchase (highest value)
2. InitiateCheckout
3. AddToCart
4. Lead
5. CompleteRegistration
6. ViewContent
7. Search
8. PageView

3. Implement Conversions API

CAPI benefits for iOS 14+:
- Not affected by ATT (App Tracking Transparency)
- No 7-day attribution limit
- Better match rates
- More reliable data

Issue 5: Event Deduplication Failures

Symptom: Same events counted twice (browser + server)

Solution: Use Event IDs

// Browser-side
const eventId = 'order_' + orderId + '_' + Date.now();

fbq('track', 'Purchase', {
  value: 99.99,
  currency: 'USD'
}, {
  eventID: eventId
});

// Server-side (same event ID)
$event = (new Event())
  ->setEventName('Purchase')
  ->setEventId('order_' . $order_id . '_' . time()) // Must match!
  ->setCustomData($customData);

Verification:

1. Events Manager > Test Events
2. Send both browser and server events
3. Verify "Event Deduplication" shows:
   - "Events Received: 2"
   - "Events Processed: 1"

Issue 6: Incorrect Event Values

Symptoms:

• Revenue in wrong currency
• Values showing as 0
• Decimal precision issues

Solutions:

Currency Mismatch

// WRONG: Mixed currencies
fbq('track', 'Purchase', {
  value: 99.99,
  currency: 'EUR'  // But value is in USD!
});

// CORRECT: Consistent currency
const orderCurrency = 'USD';
const orderValue = 99.99;

fbq('track', 'Purchase', {
  value: orderValue,
  currency: orderCurrency
});

Decimal Precision

// WRONG: Too many decimals
value: 99.999999

// CORRECT: 2 decimal places
value: parseFloat(99.999999.toFixed(2))  // 100.00

Missing Value

// WRONG: Value as string
value: '$99.99'

// CORRECT: Numeric value
value: 99.99

Tools & Debugging Resources

Essential Tools

1. Meta Pixel Helper (Chrome Extension)

Download: Chrome Web Store
Use cases:
- Verify pixel firing
- Check event parameters
- Identify errors
- View multiple pixels

2. Events Manager Test Events

Access: Events Manager > Test Events
Features:
- Real-time event monitoring
- Parameter inspection
- CAPI event validation
- Event deduplication testing

3. Meta Pixel Debugger Console

// Enable debug mode
fbq.push(['setDebug', true]);

// Or via URL parameter
https://yoursite.com?fbq_debug=1

// View debug info
fbq.getState().pixels  // Pixel configuration
fbq.getState().events  // Tracked events

4. Chrome DevTools Network Tab

1. Open DevTools (F12)
2. Network tab
3. Filter: "facebook.com/tr"
4. Examine requests:
   - Status: Should be 200
   - Method: GET or POST
   - Query params: Check event data

5. Conversions API Debugger

# Test CAPI endpoint
curl -X POST \
  'https://graph.facebook.com/v18.0/PIXEL_ID/events' \
  -H 'Authorization: Bearer ACCESS_TOKEN' \
  -d @event_payload.json \
  -w "\nHTTP Code: %{http_code}\n"

Debugging Scripts

Comprehensive Pixel Test

function debugMetaPixel() {
  console.log('=== Meta Pixel Debug Report ===');

  // 1. Check if loaded
  console.log('Pixel loaded:', typeof fbq !== 'undefined');

  if (typeof fbq === 'undefined') {
    console.error('❌ Pixel not loaded!');
    return;
  }

  // 2. Check pixel state
  const state = fbq.getState();
  console.log('Pixel ID:', state.pixels);
  console.log('Tracked events:', state.events);

  // 3. Check cookies
  const cookies = document.cookie;
  console.log('_fbp cookie:', cookies.match(/_fbp=([^;]+)/)?.[1] || 'Missing');
  console.log('_fbc cookie:', cookies.match(/_fbc=([^;]+)/)?.[1] || 'Missing');

  // 4. Test event
  fbq('track', 'PageView', {}, {
    eventID: 'debug_' + Date.now()
  });
  console.log('✓ Test event fired');

  // 5. Check for errors
  console.log('Recent errors:', window._fbq_errors || 'None');

  console.log('=== End Debug Report ===');
}

// Run diagnostic
debugMetaPixel();

Event Match Quality Calculator

function calculateEMQScore(eventData) {
  let score = 0;
  const weights = {
    email: 3,
    phone: 2,
    firstName: 1,
    lastName: 1,
    city: 0.5,
    state: 0.5,
    zip: 0.5,
    country: 0.5,
    fbc: 1,
    fbp: 1
  };

  for (const [field, weight] of Object.entries(weights)) {
    if (eventData[field]) {
      score += weight;
    }
  }

  const maxScore = Object.values(weights).reduce((a, b) => a + b, 0);
  const normalizedScore = (score / maxScore) * 10;

  console.log('EMQ Score:', normalizedScore.toFixed(1));
  console.log('Quality:',
    normalizedScore >= 8 ? 'Excellent' :
    normalizedScore >= 6 ? 'Good' :
    normalizedScore >= 4 ? 'Fair' : 'Poor'
  );

  return normalizedScore;
}

Error Code Reference

Monitoring & Alerts

Set Up Automated Monitoring

1. Event Volume Alerts

// Check for significant drops in event volume
function monitorEventVolume() {
  const today = getEventCount(0); // today
  const yesterday = getEventCount(1); // yesterday
  const lastWeek = getEventCount(7); // last week average

  const drop = (yesterday - today) / yesterday;

  if (drop > 0.3) {  // 30% drop
    sendAlert({
      type: 'Event Volume Drop',
      drop: (drop * 100).toFixed(0) + '%',
      today: today,
      yesterday: yesterday
    });
  }
}

2. EMQ Score Monitoring

Setup:
1. Events Manager > Event Match Quality
2. Review weekly trends
3. Set alerts for drops below 6.0
4. Investigate sudden decreases

3. CAPI Health Checks

// Monitor CAPI response rates
function monitorCAPIHealth() {
  $response = sendCAPIEvent($testEvent);

  if (!isset($response['events_received']) || $response['events_received'] != 1) {
    logError('CAPI Health Check Failed', $response);
    sendAlert('CAPI endpoint not responding correctly');
  }
}

// Run hourly via cron

Escalation & Support

When to Escalate

Immediate Escalation:

• Complete pixel failure (no events for 1+ hours)
• CAPI authentication errors
• Account suspended or restricted
• Policy violations

Escalate Within 24 Hours:

• EMQ score below 4.0
• 50%+ drop in event volume
• Attribution window issues
• Persistent error codes

Support Channels

1. Meta Business Help Center

URL: business.facebook.com/business/help
Topics:
- Technical issues
- Policy questions
- Account access

2. Meta Business Support (For Business Accounts)

Access: Business Settings > Support
Response time: 1-2 business days

3. Developer Documentation

Meta for Developers: developers.facebook.com/docs/meta-pixel
Conversions API: developers.facebook.com/docs/marketing-api/conversions-api

4. Community Forums

Facebook Marketing API Developers Group
Stack Overflow (#facebook-pixel tag)

Escalation Template

Subject: [URGENT] Meta Pixel Issue - Events Not Tracking

Pixel ID: 123456789
Domain: example.com
Issue: PageView events stopped firing at 2025-01-15 14:30 UTC

Details:
- Last successful event: 2025-01-15 14:25 UTC
- Events Manager shows "No activity"
- Meta Pixel Helper shows pixel active
- No recent site changes

Troubleshooting completed:
✓ Verified pixel code present
✓ Tested in multiple browsers
✓ Checked Events Manager diagnostics
✓ Reviewed domain verification
✓ CAPI events also affected

Request: Urgent investigation of pixel/account status

Business Impact: Unable to track $50K/day in ad spend

Fbtrace ID: [from most recent API call]

Preventive Maintenance

Daily Checks (Automated)

// Daily pixel health check
async function dailyPixelHealthCheck() {
  const checks = {
    pixelFiring: await checkPixelStatus(),
    eventVolume: await checkEventVolume(),
    emqScore: await checkEMQScore(),
    capiStatus: await checkCAPIStatus()
  };

  const issues = Object.entries(checks)
    .filter(([key, status]) => !status.healthy)
    .map(([key, status]) => ({ check: key, ...status }));

  if (issues.length > 0) {
    sendDailyReport(issues);
  }

  return checks;
}

Weekly Reviews

• Review Event Match Quality trends
• Check for new error codes in CAPI logs
• Verify all standard events still tracking
• Test critical conversion paths
• Review attribution window settings
• Update documentation for any changes

Monthly Audits

• Full pixel implementation review
• CAPI endpoint performance analysis
• EMQ score improvement opportunities
• iOS 14+ attribution review
• Aggregated Event Measurement configuration
• Security: Rotate access tokens
• Team training on new features

Quarterly Reviews

• Complete tracking stack audit
• Update to latest API version
• Review and optimize event priorities
• Analyze attribution model performance
• Competitive analysis of tracking capabilities
• Budget for new tools or plugins

Best Practices

Implementation Checklist

• Single pixel instance per page
• Pixel loads in <head> section
• PageView tracked on all pages
• Standard events using correct parameters
• Advanced Matching implemented
• Conversions API configured
• Event deduplication working
• Domain verified for iOS 14+
• Aggregated events prioritized
• Error monitoring in place
• Documentation maintained
• Team trained on troubleshooting

Performance Benchmarks

Related Resources

• Meta Pixel Implementation Guide
• Conversions API Setup
• Event Tracking Best Practices
• iOS 14+ Attribution Guide
• Meta Business Help Center