Hello all, my first post here.
Sadly, it was a problem with my Astra G Bertonne 1.8 125bhp petrol which motivated me to post here, in the hopes of getting some help.
I like a bit of car mechanics, although I am not an expert, as you will soon find out. So, pre-apologies if I say anything utterly wrong
So, on to the problem...
Basically, I have two symptoms:
1) In a cold start (usually the 1st of the day), the car revs stay around 1100 rpms making weird noises as if it is struggling (kind of like the noise of not all cylinders have fired up). It stays like that for a while, then after 15 seconds or so, the car gives some gas on its own on 2500rpm, and then the motor stabilizes with the normal sound below the 1000rpm. Other starts after this (as long as the car doesn't get cold after a long while) happen with no problems
2) When driving the car in the motorway, I usually go about 120 kph, around 3500rpm. At the beginning, i.e. first 20 minutes of motorway, the car develops nicely, climbing and all. However, after a while, I notice that the car somehow can't develop any further beyond the 3500rpm, and I notice some hickups. It's kind of like the ECU is not allowing more gas/air or something. The end result is that the car becomes slugish, particularly in climbs where speed reduces from 120 to 100 or less kph, where usually it would ride away easily 120+. Sometimes, the car develops normally, even after a while on the motorway. Sometimes the hickups happen at low speeds inside the city.
Both symptoms started more or less at the same time. I noticed that sometimes, during cold nights, the engine had a strange starting sound, much like in 1), but not so bad. I also noticed one particular night a strong smell of gasoline just for a second or so, and the car had its first 20m going around in hickups. After this, the next day, the dreaded yellow engine light appeared, and the engine had automatically its performance capped.
I went to this car-shop of an acquaintance, who plugged a code reader into the car. He said that there was some problems with the petrol volume controller and/or air-mass measurer, and it would be expensive to replace any of them. As he wasn't 100% sure of what the problem was, we opted for a more cheaper approach.
He replaced the car's spark plugs (which were very bad) with new ones, and gave a nice clean to the part which connects the air-filter-box to the engine, and has the "butterfly" (sorry for the translation) for controlling the air intake with the acceleration (something like that). We took the car for a ride, and it behaved correctly, but while we were talking with the motor running inside the shop, the yellow light came again. This time I was able to have a look at the codes:
He deleted them, but there was one that kept appearing. I can't effectively remember, but I think it was P0012. This error, however, did not make the yellow light appear. He told me to use the car for a while, and come back if the yellow light returned, and he would replace the expensive parts.
I have been doing other things some people suggested: I have used a injector cleaning fluid for a full deposit, and cleaned the car's air filter. I went to look up at the codes and am planning to spray up some of the contacts around the engine (one of the possible causes according to tables found in the internet for P0001 and P0002 is cabling). So, currently i am stuck with problems 1) and 2), and I really wouldn't like to fork a lot of money in parts which my "acquaintance" isn't really sure that is the root of the problem.
So, apologizing for the enormous text, can anyone share some wisdom on this?