Giulietta Timing Chain Issues Causing Power Loss

Having dealt with nearly identical symptoms on my 2011 Giulietta diesel, I can share my experience. With some basic mechanical knowledge, I initially thought it was timing chain related, but it turned out to be the crank sensor causing the synchronization issues. The symptoms matched exactly, reduced power output, increased fuel consumption, and the engine management light. The workshop confirmed the crankshaft sensor was failing to properly communicate engine position to the ECU, leading to timing and performance issues. Total repair cost was 340 Euro, which included diagnostics, parts, and labor. The repair took about 2 hours since the sensor location was a bit tricky to access. To better assist with your situation, could you share: Current mileage, Any unusual engine sounds, Whether the issue appeared suddenly or gradually, If there were any warning signs before the check engine light, Results from any diagnostic scans youve had done The timing belt and cam sensor should also be inspected as they can cause similar symptoms, but based on my experience, its worth checking the crank sensor first as its often the culprit with these symptoms on this engine.

Thanks for the follow-up. My Giulietta has 88298 KM and had its last major service 4 months ago. After reading your experience, I checked for fault codes again and got a cam sensor related error which explains the misfire and engine light issues. The timing chain was actually replaced during that service, so I am fairly confident the synchronization problems stem from the sensor rather than the chain itself. I will get the cam sensor replaced and report back on the fix and updated reference value readings from the diagnostic system.

Thanks for the update on your Giulietta. The cam sensor error code definitely aligns with those symptoms. When I had my crank sensor issue, I also initially suspected timing components, but these sensors often cause similar symptoms including misfires and reference value discrepancies. Since your timing chain was recently replaced, focusing on the cam sensor is the logical next step. In my case, after replacing the faulty sensor, the engine light cleared and power was fully restored. The new reference values showed proper synchronization between crankshaft and camshaft positions. One tip: ensure the electrical connector and wiring to the new cam sensor are thoroughly checked during installation. Poor connections can mimic sensor failure symptoms and trigger similar error codes. Looking forward to hearing if the cam sensor replacement resolves your issues. The repair should be straightforward since the sensor is more accessible than when I had to deal with my crank sensor problem.

Thanks everyone for the helpful insights. Just wanted to close the loop on this issue, the cam sensor replacement completely resolved the problem. Total repair cost was 280 Euro including parts and labor. The engine light cleared immediately and power returned to normal after the new sensor was installed. The diagnostic scan now shows proper reference values between the crankshaft and camshaft positions. Fuel consumption has returned to normal levels as well. Having the timing chain already replaced during the recent service definitely helped narrow down the culprit to the sensor issue. The repair shop confirmed the old cam sensor had degraded over time, causing incorrect signal readings that led to the engine light and performance problems. For anyone else facing similar symptoms, definitely worth checking both crank sensor and cam sensor status before assuming timing component issues. Great to have this resolved without major mechanical work being needed. Special thanks for the detailed responses that helped point me in the right direction for diagnosis and repair.