Struggling with Injector Problems on Your 1.6 VW Caddy? Here’s What You Need to Know
If you own a VW Caddy with a 1.6 TDI engine, you might have encountered some frustrating issues—rough idle, misfires, loss of power, or even clouds of blue or black smoke trailing behind you. Sound familiar? You’re not alone.
These problems often occur in vehicles equipped with the Siemens/VDO/Continental injector system (part numbers like 03L130277B, 03L130277S, 5WS40539, A2C59513554, and others). This setup isn’t exclusive to VW Caddy; it’s also found in Audi, Seat, and Skoda models with 1.6 TDI engines (codes CAYA, CAYB, CAYC, CAYD, CAYE).
So, what’s going wrong—and how can you fix it?
Common Symptoms of Injector Trouble
- Rough or unstable idle, especially when cold
- Misfires and loss of power
- Increased fuel consumption and poor efficiency
- Blue or black exhaust smoke
- Fault codes like injector circuit errors (e.g., P02xx)
What’s Causing These Issues?
Modern diesel engines operate under extreme pressure, which means even small weaknesses can lead to big problems. Here are the usual suspects:
- Seal and washer wear: High pressure causes seals and O-rings to degrade, leading to leaks.
- Improper fitment: Poorly seated washers allow combustion gases to escape.
- Electrical failures: The injector’s solenoid or coil can fail, requiring replacement.
- Wiring and connector faults: Damaged connectors or wiring can disrupt injector performance.
How to Fix the Problem
- Swap injectors between cylinders to see if the fault follows the injector.
- Get the injectors tested—compare repair costs versus replacement costs.
- Replace faulty connectors or wiring (e.g., parts like 50D250-Q-W or 18D406).
- Install new seals and clamp kits for proper refitting.
- Code the injector into the ECU after replacement.
- Re-seal correctly using quality parts like copper washers (27D173) and leak-off seals (CMR114).
- Replace bolts and clamps with a proper clamp kit (03L-CLAMP KIT).
Prevent Future Problems
- Use high-quality diesel fuel.
- Regularly inspect fuel lines, filters, priming pump, and rail for leaks.
- Avoid contamination and don’t delay filter changes—poor maintenance shortens injector life.
Replacement Parts Available
- Copper seating washer: 27D173
- Nozzle nut: CMR545
- Leak off clip: CMR512
- Body O-ring: 5855-30FX
- Electrical connector: 50D250-Q-W
- Nozzle: PM011
- Engine seal: 18D865
- Clamp kit: 03L-CLAMP KIT
- Solenoid O-ring: CMR514
- Inlet washer: CMR518
- Leak-off connectors (metal): 18D406
- Leak-off connectors (plastic): 18D406-P
- Leak-off O-ring: CMR114
- Back leak pressure valve for leak off pipe: 18D9100
- Solenoid cap: 28D40
Final Thoughts
Injector problems can be a headache, but with the right approach—diagnosis, quality parts, and proper installation—you can restore your VW Caddy’s performance and prevent future issues. If you’re unsure, consult a trusted diesel specialist for testing and repairs.
Vehicles with the 1.6 TDI Engine
| VEHICLE | ENGINE CODES | MODEL YEAR | KW | HP | DESIGN |
| AUDI 1.6 | |||||
| A1 8X1, 8XK | CAYC | 05.2010-04.2015 | 77 | 105 | HATCHBACK |
| A1 8X1, 8XK | CAYB | 03.2011-04.2015 | 66 | 90 | HATCHBACK |
| A1 SPORTBACK 8XA, 8XF | CAYC | 11.2011-04.2015 | 77 | 105 | HATCHBACK |
| A1 SPORTBACK 8XA, 8XF | CAYB | 11.2011-04.2015 | 66 | 90 | HATCHBACK |
| A3 8P1 | CAYC | 05.2009-08.2012 | 77 | 105 | HATCHBACK |
| A3 8P1 | CAYB | 05-2009-08.2012 | 66 | 90 | HATCHBACK |
| A3 CONVERTIBLE 8P7 | CAYC | 05.2009-05.2013 | 77 | 105 | CONVERTIBLE |
| A3 SPORTBACK 8PA | CAYC | 05.2009-03.2013 | 77 | 105 | HATCHBACK |
| A3 SPORTBACK 8PA | CAYB | 05.2009-03.2013 | 66 | 90` | HATCHBACK |
| SEAT 1.6 | |||||
| ALTEA 5P1 | CAYC | 10.2009-07.2015 | 77 | 105 | MPV |
| ALTEA 5P1 | CAYB | 11.2010-07.2015 | 66 | 90 | MPV |
| ALTEA XL 5P5, 5P8 | CAYC | 10.2009-07.2015 | 77 | 105 | MPV |
| ALTEA XL 5P5, 5P8 | CAYC | 11.2010-07.2015 | 66 | 90 | MPV |
| IBIZA IV 6J5, 6P1 | CAYB | 05.2009-05.2015 | 77 | 105 | HATCHBACK |
| IBIZA IV 6J5, 6P1 | CAYB | 05.2009-05.2015 | 66 | 90 | HATCHBACK |
| IBIZA IV SC 6J1, 6P5 | CAYC | 05.2009-05.2015 | 77 | 105 | HATCHBACK |
| IBIZA IV ST 6J8, 6P8 | CAYB | 03.2010-05.2015 | 66 | 90 | ESTATE |
| LEON 1P1 | CAYC | 02.2010-12.2012 | 77 | 105 | HATCHBACK |
| LEON 1P1 | CAYB | 11.2010-12.2012 | 66 | 90 | HATCHBACK |
| TOLEDO IV KG3 | CAYC CLNA | 07.2012-06.2015 | 77 | 105 | HATCHBACK |
| TOLEDO IV KG3 | – | 06.2013-06.2015 | 66 | 90 | HATCHBACK |
| SKODA 1.6 | |||||
| FABIA II 542 | CAYC | 03.2010-12.2014 | 77 | 105 | HATCHBACK |
| FABIA II 542 | CAYB | 03.2010-12.2014 | 66 | 90 | HATCHBACK |
| FABIA II 542 | CAYA | 04.2010-12.2014 | 55 | 75 | HATCHBACK |
| FABIA II COMBI 545 | CAYC | 03.2010-12.2014 | 77 | 105 | ESTATE |
| FABIA II COMBI 545 | CAYB | 03.2010-12.2014 | 66 | 90 | ESTATE |
| FABIA II COMBI 545 | CAYA | 04.2010-12.2014 | 55 | 75 | ESTATE |
| FABIA II PRAKTIK 545 | CAYA | 10.2013-11.2014 | 55 | 77 | ESTATE VAN |
| OCTAVIA 1Z3 | CAYC | 06.2009-04.2013 | 77 | 105 | HATCHBACK |
| OCTAVIA II COMBI 1Z5 | CAYC | 06.2009-04.2013 | 77 | 105 | ESTATE |
| OCTAVIA II COMBI 1Z5 | CAYC | 06.2009-04.2013 | 77 | 105 | ESTATE |
| OCTAVIA II COMBI 4X4 1Z5 | CAYC | 06.2009-04.2013 | 77 | 105 | ESTATE |
| RAPID NH3, NK3, NK6 | CAYB | 08.2013-05.2015 | 66 | 90 | HATCHBACK |
| RAPID SPACEBACK NH1 | – | 07-2012-12-2019 | 77 | 105 | HATCHBACK |
| RAPID SPACEBACK NH1 | – | 08.2013-05.2015 | 66 | 90 | HATCHBACK |
| ROOMSTER 5J7 | CAYC | 03.2010-05.2015 | 77 | 105 | MPV |
| ROOMSTER 5J7 | CAYB | 03.2010-05.2015 | 66 | 90 | MPV |
| ROOMSTER PRAKTIK 5J | CAYB | 03.2010-05.2015 | 66 | 90 | ESTATE VAN |
| SUPERB II 3T4 | CAYC | 09.2010-05.2015 | 77 | 105 | HATCHBACK |
| SUPERB II ESTATE 3T5 | CAYC | 09.2010-05.2015 | 77 | 105 | ESTATE |
| YETI 5L | CAYC | 11.2010-05.2015 | 77 | 105 | SUV |
| VW 1.6 | |||||
| BEETLE 5C1, 5C2 | CAYC | 10.2011-07.2016 | 77 | 105 | HATCHBACK |
| BEETLE CONVERTIBLE 5C7, 5C8 | CAYC | 12.2011-07.2016 | 77 | 105 | CONVERTIBLE |
| CADDY ALLTRACK IV BOX BODY/MPV SAA | CAYD | 05.2015-09.2020 | 75 | 102 | BOX BDY/MPV |
| CADDY ALLTRACK IV BOX BODY/MPV SAA | CAYE | 05.2015-11-2017 | 55 | 75 | BOX BDY/MPV |
| CADDY ALLTRACK IV MPV SAB | CAYD | 05.2015-09.2020 | 75 | 102 | MPV |
| CADDY III BOX BODY/MPV 2KA, 2KH, 2CA, 2CH | CAYD | 08.2010-05.2015 | 75 | 102 | BOX BODY/MPV |
| CADDY III BOX BODY/MPV 2KA, 2KH, 2CA, 2CH | CAYE | 08.2010-05.2015 | 55 | 75 | BOX BODY/MPV |
| CADDY III MPV 2KB, 2KJ, 2CB, 2CJ | CAYD | 08.2010-05.2015 | 75 | 102 | MPV |
| CADDY III MPV 2KB, 2KJ, 2CB, 2CJ | CAYE | 08.2010-05.2015 | 55 | 75 | MPV |
| CADDY IV BOX BODY/MPV SAA, SAH | CAYD | 05.2015-09.2020 | 75 | 102 | BOX BODY/MPV |
| CADDY IV BOX BODY/MPV SAA, SAH | CAYE | 05.2015-11.2017 | 55 | 75 | BOX BODY/MPV |
| CADDY IV MPV SAB, SAJ | CAYD | 05.2015-09.2020 | 75 | 102 | MPV |
| CADDY IV MPV SAB, SAJ | CAYE | 05.2015-11.2017 | 55 | 75 | MPV |
| GOLF PLUS V 5M1, 521 | CAYC | 03.2009-12.2013 | 77 | 105 | HATCHBACK |
| GOLF PLUS V 5M1, 521 | CAYB | 03.2009-12.2013 | 66 | 90 | HATCHBACK |
| GOLF VAN VI VARIANT AJ5 | CAYC | 07.2009-05.2014 | 77 | 105 | ESTATE VAN |
| GOLF VI 5K1 | CAYC | 02.2009-11.2012 | 77 | 105 | HATCHBACK |
| GOLF VI 5K1 | CAYB | 02.2009-11.2012 | 66 | 90 | HATCHBACK |
| GOLF VI CONVERTIBLE 517 | CAYC | 03.2011-05.2016 | 77 | 105 | CONVERTIBLE |
| GOLF VI VARIANT AJ5 | CAYC | 07.2009-07.2013 | 77 | 105 | ESTATE |
| GOLF VI VARIANT AJ5 | CAYB | 12.2009-07.2013 | 66 | 90 | ESTATE |
| GOLF VI VARIANT 4MOTION AJ5 | CAYC | 07.2009-01.2012 | 77 | 105 | ESTATE |
| JETTA III 1K2 | CAYC | 06.2009-10-2010 | 77 | 105 | SALOON |
| JETTA III 1K2 | CAYB | 12.2009-10-2010 | 66 | 90 | SALOON |
| JETTA IV 162, 163, AV3, AV2 | CAYC | 04.2010-07.2015 | 77 | 105 | SALOON |
| PASSAT B6 3C2 | CAYC | 08.2009-07.2010 | 77 | 105 | SALOON |
| PASSAT B6 VARIANT 3C5 | CAYC | 08.2009-2010 | 77 | 105 | ESTATE |
| PASSAT B7 362 | CAYC | 0.-2010-12.2014 | 77 | 105 | SALOON |
| PASSAT B7 VARIANT 365 | CAYC | 08.2010-12.2014 | 77 | 105 | ESTATE |
| POLO V 6R1, 6C1 | CLNA CAYC | 06.2009-08.2015 | 77 | 105 | HATCHBACK |
| POLO V 6R1, 6C1 | CAYB | 06.2009-05.2014 | 66 | 90 | HATCHBACK |
| POLO V 6R1, 6C1 | CLNA CAYC | 06.2009-05.201 | 55 | 75 | HATCHBACK |
| TOURAN 1T3 | CAYB | 05.2010-05.2015 | 66 | 9 | MPV |




