Vauxhall Combo Persistent DPF Fault P1206 & P24A4

Vauxhall Combo DPF Fault: From Repeated Cleans to a Clear Diagnosis A Vauxhall Combo came in after a long run of frustration. It had been to several garages for the same DPF (Diesel Particulate Filter) issue, cleaned three times, then back to square one within a couple of days. This is the Vauxhall version of a van also sold under other badges, like Fiat, so there is shared tech under the skin. The goal was simple, find the cause, not just clean it again. * Cleaned three times * Light returns after 2 to 3 days * No lasting fix Getting Started: Initial Engine Assessment The van is a 1.3 CDTI, Euro 6, on an 18 plate with stop-start. The engine light was on from the start. Time to move straight to diagnostics. Introducing the Diagnostic Tool A MuCar 892BT was used for a full system scan. It runs on a Launch-style platform and talks to Opel systems without fuss. you can buy this scan tool here.. https://mythinkcar.com/?ref=dnnktcax discount code JIMMYORILEY 1. Enter the update section 2. Select auto search 3. Choose Opel Combo D Check the video description for the tool link and discount. Scanning for Fault Codes Primary Fault: P24A4 Explained The scan flagged P24A4, a particle filter differential pressure sensor circuit fault. The system also showed a long distance since the DPF indicator came on, about 792 km without a regen. Recurring P1206 Code The customer also reported a returning P1206 fault after previous cleans. Spraying cleaner into a clogged filter is not a fix if the cause remains. * P24A4: Sensor circuit problem * P1206: Filter clog indicator that returns after short use Analyser’s View: Live Data Live data told its own story. The DPF pressure sat at 60 mbar, high at idle, with no regen attempt logged for hundreds of kilometres. Oddly, the sensor still read values despite the earlier sensor circuit fault. The unexpected sensor readings made it worth cross-checking. Cross-Checking with Fiat System Switching to the Fiat menu confirmed the same result, particle filter clogged. This helps to rule out brand-specific descriptions and keeps focus on the fault. * Confirms clog * Rules out menu-based error Visual Inspection with Borescope A borescope check showed no visible damage upfront to the catalyst. The turbo side was clean with no oil passing. The DPF face could not be seen, so the next step was in-situ cleaning. Attempting In-Situ Cleaning Fluid Application Process Cleaning fluid was fed through the DPF pressure sensor port using Launch UK fluid, with the compressor at about 8 to 9 bar. The engine was held at 3,000 rpm during the process. Monitoring Pressure Drop Pressure dropped towards 40 to 50 mbar under load, but idle stayed around 12 to 13 mbar, still too high. Soot accumulation climbed to 492 percent as the ECU still saw excessive pressure. * Inject fluid * Hold revs * Check readings Resetting and Test Drive The DPF and engine oil counters were reset so the ECU could authorise regen. A 15 km drive left pressure at 21 mbar and soot at 111 percent. The fluctuating pressure confirmed the problem was still present. Removing and Examining the DPF Disassembly Insights The DPF was removed. There was no oil from the turbo, only soot. A little oil staining around the turbo gasket was noted. Off-Vehicle Cleaning Trial On the Carbon Clean DCS16 machine, very little water flowed through. The filter media began to crumble into dust. Irreparable damage found. Aftermath and Next Steps With no replacement unit available from suppliers that day, the old DPF was refitted. It showed about 10 to 11 mbar at idle, yet it still needs a new DPF to resolve the fault. A new unit will be fitted once sourced. In short, repeated cleaning masked a failing DPF that had broken down internally. The fix is replacement, not another flush.