Opel Signum
Base V6 turbo without VCT. Same block as Z28NET but with lower output. Timing chain subject is identical to the Z28NET.
Luxury glider with V6
Comfortable long-distance car with a powerful V6. More cruiser than sportster.
Engine Weaknesses 4
Both timing chains on the 2.8 V6 stretch from 100,000–150,000 km. Oil channel blockage can accelerate the wear. Preventive replacement recommended.
Symptoms: Rattling on cold start, engine warning light, limp mode, valve damage in extreme cases
The V6 is prone to misfires and juddering at warm idle. Replacing spark plugs and coils does not always provide a permanent fix.
Symptoms: Juddering at idle (warm), brief jolting of the vehicle, lambda values within normal range
Wastegate actuator and turbine shaft deteriorate at higher mileage. Power loss and fluctuating boost pressure.
Symptoms: Uneven boost pressure, power loss in the mid-range, occasional limp mode
Fault code for camshaft position bank 2. Often a faulty sensor, but can also indicate mechanical problems (timing chain).
Symptoms: Engine warning light, fault codes P0340/P0345, slight rough running
Vehicle Weaknesses 12
Electronically controlled ZF-Sachs dampers fail around 90,000–130,000 km. OEM parts over 1,600 €; aftermarket from 150 € per unit.
At the rear roof rail end cap, moisture penetrates between two sheet metal layers causing corrosion.
Cold solder joints in the CIM cause intermittent warning lights without actual fault. Diagnosis requires specialist equipment (Tech2).
On the Signum 1.9 CDTI the EGR valve and swirl flaps clog with soot deposits, causing power loss and smoke. Removal and cleaning costs approx. 100–200 €; replacement is more expensive.
The main radiator of the Signum rusts and leaks from approx. 150,000 km. Radiator replacement requires complete front-end disassembly including AC condenser.
KBA recall for Vectra C and Signum (build years 2002–2007): insufficient spring force in the handbrake lever ratchet.
Track rods and track rod ends show play from approx. 100,000 km. Parts are inexpensive but wheel alignment must be done afterwards.
Rotary knob potentiometers develop contact weaknesses through cold solder joints. Blower occasionally fails completely.
Even without IDS, shock absorbers wear from approx. 100,000–130,000 km. Short-trip use accelerates wear.
The electro-hydraulic steering rack (EHPS) of the Signum leaks oil from approx. 140,000 km. Dashboard warning; sudden loss of steering assistance possible when oil level empty.
On the Signum water enters through leaking tailgate seals or rear light seals into the boot. Spare wheel well fills up.
In the Signum the adhesive between the headliner support rails and fabric deteriorates after 15–20 years due to heat. Foam crumbles; fabric droops.
