Opel Signum
Reliable turbopetrol engine from the Ecotec family. The chain tensioner on early pre-facelift engines is a known weak point and should be preventively replaced by the revised component (from MY 2009, part no. 12608580).
Signum turbo
129 kW in the Signum – effortless cruising with turbo muscle.
Engine Weaknesses 4
Pre-facelift engines have a hydraulic chain tensioner that can seize. The auxiliary chain guide rail snaps off; broken pieces fall into the oil sump. From model year 2009, Opel fitted the revised tensioner (part no. 12608580).
Symptoms: Rattling or clattering immediately after cold start, easing after approx. 30 seconds; engine warning light on advanced damage
With neglected oil supply or after bypass valve problems, the turbocharger can fail. A new unit from an Opel dealer costs approx. 1,250 EUR without fitting. Labour-intensive as turbo removal requires many additional tasks.
Symptoms: No boost pressure, severe power loss at higher revs, whistling or rattling noise from turbo, blue exhaust smoke
The bypass valve membrane develops a tear. The turbocharger can no longer regulate boost pressure correctly. The fault occurs intermittently and can temporarily disappear before becoming permanent. Two valves fitted: one on the turbo, one on the throttle body.
Symptoms: Intermittent power loss under load, bypass valve regulation out of target range fault message, delayed response when accelerating
The water pump sits behind the turbocharger and auxiliary chain and is difficult to access. On failure, considerable labour costs arise as the turbo and auxiliary timing chain cover must be removed. Coolant loss can lead to overheating damage.
Symptoms: Coolant loss, dropping coolant levels with no visible leak, temperature rise, coolant smell with warm engine
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.
