In my younger days, I did a fair bit of stripping engines, and even reconditioned an automatic box once - but that was all when cars still had carburetors, points and distributors. I don't know much at all about diesels apart from their theoretical principles.
Now, after 10 years since new, I have had a run of bad luck with my Citroen Xsara Picasso 1.6 HDi (2006).
The car had never given any trouble, but at 10 years, I replaced the timing belt, which involved moving the steering fluid reservoir on its rubber tubes, which dislodged a but of dirt that jammed the pressure by-pass valve in the steering pump. You can't get the valve, so I replaced the pump, which involved uncoupling 4 electrical connectors (I think to do with the a/c and the EGR - though I'm not sure), and after that job, the engine light came on, so I suspected a connector problem. After two very short trips, it went out again, but it left me with poor acceleration, and I have also noticed a drop in the dashboard indication of fuel consumption (down from 60 MPG to 42.8). I bought a cheap scanner on Ebay, and the diagnostics showed ...
Code: Select all
stored trouble codes | pending codes
p0100 mass volume airflow circuit malfunction | p3008 unknown code
p0299 turbo underboost | p0299 turbo underboost
p0238 turbo sensor A-circuit high | p1351 unknown code
p1351 unknown diagnostic code
I cleared these codes to see if the poor performance was due to the EMU limiting it due to the stored codes, and took the car for a 5-mile burn. Performance was still poor, and when I got home again, I re-checked the fault codes. There were none, but the three "pending" codes were back again. They are P3008, P0299, P1351.
The possibilities are :
1. something went wrong when I disconnected / reconnected the electrical connectors
2. I made an error while changing the timing belt. I know that bad valve timing screws with performance - I once bought a Mini with poor performance, and found it was one tooth out on the timing chain. On the Citroen, I marked the belt and pulleys with paint, and was very careful to fit the new belt exactly as the original one had been fitted. However, could somebody tell me whether bad valve timing would cause error codes to be generated? As I don't currently have any, can I assume that the belt is definitely not a tooth out?